Linux Virtual Delivery Agent

Install the Linux VDA on Debian manually

Important:

For fresh installations, we recommend you use easy install for a quick installation. Easy install saves time and labor and is less error-prone than the manual installation detailed in this article.

Step 1: Prepare configuration information and the Linux machine

Step 1a: Set the host name

To make sure that the host name of the machine is reported correctly, change the /etc/hostname file to contain only the host name of the machine.

hostname

Step 1b: Assign a loopback address to the host name

Make sure that the DNS domain name and Fully Qualified Domain Name (FQDN) of the machine are reported back correctly. The way is to change the following line of the /etc/hosts file to include the FQDN and host name as the first two entries:

127.0.0.1 hostname-fqdn hostname localhost

For example:

127.0.0.1 vda01.example.com vda01 localhost

Remove any other references to hostname-fqdn or hostname from other entries in the file.

Note:

The Linux VDA currently does not support NetBIOS name truncation. The host name must not exceed 15 characters.

Tip:

Use a–z, A–Z, 0–9, and hyphen (-) characters only. Avoid underscores (_), spaces, and other symbols. Do not start a host name with a number and do not end with a hyphen. This rule also applies to Delivery Controller host names.

Step 1c: Check the host name

Restart the machine and verify that the host name is set correctly:

hostname
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This command returns only the host name of the machine and not its FQDN.

Verify that the FQDN is set correctly:

hostname -f
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This command returns the FQDN of the machine.

Step 1d: Disable multicast DNS

The default settings have multicast DNS (mDNS) enabled, which can lead to inconsistent name resolution results.

To disable mDNS, edit /etc/nsswitch.conf and change the line:

hosts: files mdns_minimal [NOTFOUND=return] dns

To:

hosts: files dns

Step 1e: Check name resolution and service reachability

Verify that you can resolve the FQDN and ping the domain controller and Delivery Controller:

nslookup domain-controller-fqdn

ping domain-controller-fqdn

nslookup delivery-controller-fqdn

ping delivery-controller-fqdn
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If you cannot resolve the FQDN or ping either of these machines, review the steps before proceeding.

Step 1f: Configure clock synchronization (chrony)

Maintaining accurate clock synchronization between the VDAs, Delivery Controllers and domain controllers is crucial. Hosting the Linux VDA as a virtual machine (VM) can cause clock skew problems. For this reason, synchronizing time with a remote time service is preferred.

Install chrony:

apt-get install chrony
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As a root user, edit /etc/chrony/chrony.conf and add a server entry for each remote time server:

server peer1-fqdn-or-ip-address iburst
server peer2-fqdn-or-ip-address iburst

In a typical deployment, synchronize time from the local domain controllers and not directly from public NTP pool servers. Add a server entry for each Active Directory domain controller in the domain.

Remove any other server or pool entries listed including loopback IP address, localhost, and public server *.pool.ntp.org entries.

Save changes and restart the Chrony daemon:

sudo systemctl restart chrony
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Step 1g: Install packages

sudo apt-get install -y libsasl2-2

sudo apt-get install -y libgtk2.0-0
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Step 1h: Add repositories to install necessary dependencies

For Debian 11, add the deb http://deb.debian.org/debian/ bullseye main line to the /etc/apt/sources.list file.

Step 1i: Install and specify a database to use

Note:

  • We recommend you use SQLite for VDI mode only and use PostgreSQL for a hosted shared desktops delivery model.

  • For easy install and MCS, you can specify SQLite or PostgreSQL to use without having to install them manually. Unless otherwise specified through /etc/xdl/db.conf, the Linux VDA uses PostgreSQL by default.

  • For manual installations, you must install SQLite, PostgreSQL, or both manually. If you install both SQLite and PostgreSQL, you can specify one of them to use by editing /etc/xdl/db.conf after installing the Linux VDA package.

This section describes how to install PostgreSQL and SQLite and how to specify either of them to use.

Install PostgreSQL

Run the following commands to install PostgreSQL:

sudo apt-get update

sudo apt-get install -y postgresql

sudo apt-get install -y libpostgresql-jdbc-java
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Run the following commands to start PostgreSQL upon machine startup or immediately, respectively:

sudo systemctl enable postgresql

sudo systemctl start postgresql
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Install SQLite

For Debian, run the following command to install SQLite:

sudo apt-get install -y sqlite3
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Specify a database to use

If you install both SQLite and PostgreSQL, you can specify one of them to use by editing /etc/xdl/db.conf after installing the Linux VDA package.

  1. Run /opt/Citrix/VDA/sbin/ctxcleanup.sh. Omit this step if it is a fresh installation.
  2. Edit /etc/xdl/db.conf to specify a database to use.
  3. Run ctxsetup.sh.

Note:

You can also use /etc/xdl/db.conf to configure the port number for PostgreSQL.

Step 2: Prepare the hypervisor

Some changes are required when running the Linux VDA as a VM on a supported hypervisor. Make the following changes based on the hypervisor platform in use. No changes are required if you are running the Linux machine on bare metal hardware.

Fix time synchronization on XenServer (formerly Citrix Hypervisor)

When the XenServer Time Sync feature is enabled, within each paravirtualized Linux VM you experience issues with NTP and XenServer. Both try to manage the system clock. To avoid the clock becoming out of sync with other servers, make sure that the system clock within each Linux guest is synchronized with the NTP. This case requires disabling host time synchronization. No changes are required in HVM mode.

If you are running a paravirtualized Linux kernel with XenServer VM Tools installed, you can check whether the XenServer Time Sync feature is present and enabled from within the Linux VM:

su -
cat /proc/sys/xen/independent_wallclock
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This command returns 0 or 1:

  • 0 - The time sync feature is enabled, and must be disabled.
  • 1 - The time sync feature is disabled, and no further action is required.

If the /proc/sys/xen/independent_wallclock file is not present, the following steps are not required.

If enabled, disable the time sync feature by writing 1 to the file:

sudo echo 1 > /proc/sys/xen/independent_wallclock
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To make this change permanent and persistent after restart, edit the /etc/sysctl.conf file and add the line:

xen.independent_wallclock = 1

To verify these changes, restart the system:

su -
cat /proc/sys/xen/independent_wallclock
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This command returns the value 1.

Fix time synchronization on Microsoft Hyper-V

Linux VMs with Hyper-V Linux Integration Services installed can use the Hyper-V time synchronization feature to use the host operating system’s time. To ensure that the system clock remains accurate, enable this feature alongside NTP services.

From the management operating system:

  1. Open the Hyper-V Manager console.
  2. For the settings of a Linux VM, select Integration Services.
  3. Ensure that Time synchronization is selected.

Note:

This approach is different from VMware and XenServer (formerly Citrix Hypervisor), where host time synchronization is disabled to avoid conflicts with NTP. Hyper-V time synchronization can coexist and supplement NTP time synchronization.

Fix time synchronization on ESX and ESXi

When the VMware Time Synchronization feature is enabled, within each paravirtualized Linux VM you experience issues with the NTP and the hypervisor. Both try to synchronize the system clock. To avoid the clock becoming out of sync with other servers, ensure that the system clock within each Linux guest is synchronized with the NTP. This case requires disabling host time synchronization.

If you are running a paravirtualized Linux kernel with VMware Tools installed:

  1. Open the vSphere Client.
  2. Edit settings for the Linux VM.
  3. In the Virtual Machine Properties dialog, open the Options tab.
  4. Select VMware Tools.
  5. In the Advanced box, clear Synchronize guest time with host.

Step 3: Add the Linux VM to the Windows domain

The following methods are available for adding Linux machines to the Active Directory (AD) domain:

Follow instructions based on your chosen method.

Note:

Session launches might fail when the same user name is used for the local account in the Linux VDA and the account in AD.

Samba Winbind

Install or update the required packages

sudo apt-get install winbind samba libnss-winbind libpam-winbind krb5-config krb5-locales krb5-user
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Enable the Winbind daemon to start on machine startup

The Winbind daemon must be configured to start on machine startup:

sudo systemctl enable winbind
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Note:

Ensure that the winbind script is located under /etc/init.d.

Configure Kerberos

Open /etc/krb5.conf as a root user, and make the following settings:

Note:

Configure Kerberos based on your AD infrastructure. The following settings are meant for the single-domain, single-forest model.

[libdefaults]

default_realm = REALM

dns_lookup_kdc = false

[realms]

REALM = {

admin_server = domain-controller-fqdn

kdc = domain-controller-fqdn

}

[domain_realm]

domain-dns-name = REALM

.domain-dns-name = REALM

The domain-dns-name parameter in this context is the DNS domain name, such as example.com. The REALM is the Kerberos realm name in uppercase, such as EXAMPLE.COM.

Configure Winbind Authentication

Open /etc/samba/smb.conf by running the vim /etc/samba/smb.conf command, and then make the following settings:

[global]

workgroup = WORKGROUP

security = ADS

realm = REALM

encrypt passwords = yes

idmap config *:range = 16777216-33554431

kerberos method = secrets and keytab

winbind refresh tickets = yes

template shell = /bin/bash

WORKGROUP is the first field in REALM, and REALM is the Kerberos realm name in uppercase.

Configure nsswitch

Open /etc/nsswitch.conf, and append winbind to the following lines:

passwd: files systemd winbind
group: files systemd winbind

Join Windows domain

Your domain controller must be reachable and you must have an Active Directory user account with permissions to add computers to the domain:

sudo net ads join <Kerberos realm name in uppercase> -U <domain user with permission to add computers to the domain>
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Restart Winbind

sudo systemctl restart winbind
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Configure PAM for Winbind

Run the following command and ensure that the Winbind NT/Active Directory authentication and Create home directory on login options are selected:

sudo pam-auth-update
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Tip:

The winbind daemon stays running only if the machine is joined to a domain.

Verify domain membership

The Delivery Controller requires that all VDA machines, whether Windows or Linux, have a computer object in Active Directory.

Run the net ads command of Samba to verify that the machine is joined to a domain:

sudo net ads testjoin
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Run the following command to verify extra domain and computer object information:

sudo net ads info
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Verify Kerberos configuration

To verify that Kerberos is configured correctly for use with the Linux VDA, verify that the system keytab file has been created and contains valid keys:

sudo klist -ke
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This command displays the list of keys available for the various combinations of principal names and cipher suites. Run the Kerberos kinit command to authenticate the machine with the domain controller using these keys:

sudo kinit -k MACHINE\$@REALM
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The machine and realm names must be specified in uppercase. The dollar sign ($) must be escaped with a backslash (\) to prevent shell substitution. In some environments, the DNS domain name is different from the Kerberos realm name. Ensure that the realm name is used. If this command is successful, no output is displayed.

Verify that the TGT ticket for the machine account has been cached using:

sudo klist
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Examine the account details of the machine using:

sudo net ads status
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Verify user authentication

Use the wbinfo tool to verify that domain users can authenticate with the domain:

wbinfo --krb5auth=domain\\username%password
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The domain specified here is the AD domain name, not the Kerberos realm name. For the bash shell, the backslash (\) character must be escaped with another backslash. This command returns a message indicating success or failure.

To verify that the Winbind PAM module is configured correctly, log on to the Linux VDA using a domain user account that has not been used before.

ssh localhost -l domain\\username

id -u
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Note:

To run an SSH command successfully, ensure that SSH is enabled and working properly.

Verify that a corresponding Kerberos credential cache file was created for the uid returned by the id -u command:

ls /tmp/krb5cc_uid
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Verify that the tickets in the user’s Kerberos credential cache are valid and not expired:

klist
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Exit the session.

exit
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A similar test can be performed by logging on to the Gnome or KDE console directly. Proceed to Step 6: Install the Linux VDA after the domain joining verification.

Tip:

If you succeed in user authentication but cannot show your desktop when logging on with a domain account, restart the machine and try again.

Quest authentication service

Configure Quest on domain controller

Assume that you have installed and configured the Quest software on the Active Directory domain controllers, and have been granted administrative privileges to create computer objects in Active Directory.

Enable domain users to log on to Linux VDA machines

To enable domain users to establish HDX sessions on a Linux VDA machine:

  1. In the Active Directory Users and Computers management console, open Active Directory user properties for that user account.
  2. Select the Unix Account tab.
  3. Check Unix-enabled.
  4. Set the Primary GID Number to the group ID of an actual domain user group.

Note:

These instructions are equivalent for setting up domain users for logon using the console, RDP, SSH, or any other remoting protocol.

Configure Quest on Linux VDA

Work around SELinux policy enforcement

The default RHEL environment has SELinux fully enforced. This enforcement interferes with the Unix domain socket IPC mechanisms used by Quest, and prevents domain users from logging on.

The convenient way to work around this issue is to disable SELinux. As a root user, edit /etc/selinux/config and change the SELinux setting:

SELINUX=disabled

This change requires a machine restart:

reboot
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Important:

Use this setting carefully. Reenabling SELinux policy enforcement after disabling can cause a complete lockout, even for the root user and other local users.

Configure VAS daemon

Autorenewal of Kerberos tickets must be enabled and disconnected. Authentication (offline logon) must be disabled:

sudo /opt/quest/bin/vastool configure vas vasd auto-ticket-renew-interval 32400

sudo /opt/quest/bin/vastool configure vas vas_auth allow-disconnected-auth false
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This command sets the renewal interval to nine hours (32,400 seconds) which is one hour less than the default 10-hour ticket lifetime. Set this parameter to a lower value on systems with a shorter ticket lifetime.

Configure PAM and NSS

To enable domain user logon through HDX and other services such as su, ssh, and RDP, run the following commands to configure PAM and NSS manually:

sudo /opt/quest/bin/vastool configure pam

sudo /opt/quest/bin/vastool configure nss
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Join Windows domain

Join the Linux machine to the Active Directory domain using the Quest vastool command:

sudo /opt/quest/bin/vastool -u user join domain-name
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The user is any domain user with permissions to join computers to the Active Directory domain. The domain-name is the DNS name of the domain, for example, example.com.

Restart the Linux machine after domain joining.

Verify domain membership

The Delivery Controller requires that all VDA machines, whether Windows or Linux, have a computer object in Active Directory. To verify that a Quest-joined Linux machine is on the domain:

sudo /opt/quest/bin/vastool info domain
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If the machine is joined to a domain, this command returns the domain name. If the machine is not joined to any domain, the following error appears:

ERROR: No domain could be found.
ERROR: VAS_ERR_CONFIG: at ctx.c:414 in _ctx_init_default_realm
default_realm not configured in vas.conf. Computer may not be joined to domain

Verify user authentication

To verify that Quest can authenticate domain users through PAM, log on to the Linux VDA using a domain user account that has not been used before.

ssh localhost -l domain\\username

id -u
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Verify that a corresponding Kerberos credential cache file was created for the UID returned by the id -u command:

ls /tmp/krb5cc_uid
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Verify that the tickets in the Kerberos credential cache are valid and not expired:

/opt/quest/bin/vastool klist
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Exit the session.

exit
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Proceed to Step 6: Install the Linux VDA after the domain-joining verification.

Centrify DirectControl

Join Windows domain

With the Centrify DirectControl Agent installed, join the Linux machine to the Active Directory domain using the Centrify adjoin command:

su –
adjoin -w -V -u user domain-name
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The user parameter is any Active Directory domain user with permissions to join computers to the Active Directory domain. The domain-name parameter is the name of the domain to join the Linux machine to.

Verify domain membership

The Delivery Controller requires that all VDA machines, whether Windows or Linux, have a computer object in Active Directory. To verify that a Centrify-joined Linux machine is on the domain:

su –

adinfo
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Verify that the Joined to domain value is valid and the CentrifyDC mode returns connected. If the mode remains stuck in the starting state, then the Centrify client is experiencing server connection or authentication problems.

More comprehensive system and diagnostic information is available using:

adinfo --sysinfo all

adinfo --diag
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Test connectivity to the various Active Directory and Kerberos services.

adinfo --test
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Proceed to Step 6: Install the Linux VDA after the domain-joining verification.

SSSD

Configure Kerberos

Run the following command to install Kerberos:

sudo apt-get install krb5-user
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To configure Kerberos, open /etc/krb5.conf as root and set the parameters:

Note:

Configure Kerberos based on your AD infrastructure. The following settings are meant for the single-domain, single-forest model.

[libdefaults]

default_realm = REALM

dns_lookup_kdc = false

rdns = false

[realms]

REALM = {

admin_server = domain-controller-fqdn

kdc = domain-controller-fqdn

}

[domain_realm]

domain-dns-name = REALM

.domain-dns-name = REALM

The domain-dns-name parameter in this context is the DNS domain name, such as example.com. The REALM is the Kerberos realm name in uppercase, such as EXAMPLE.COM.

Join the domain

SSSD must be configured to use Active Directory as its identity provider and Kerberos for authentication. However, SSSD does not provide AD client functions for joining the domain and managing the system keytab file. You can use adcli, realmd, or Samba instead.

Note:

This section only provides information for adcli and Samba.

  • If you use adcli to join the domain, complete the following steps:
  1. Install adcli.

    sudo apt-get install adcli
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  2. Join the domain with adcli.

    Remove the old system keytab file and join the domain using:

    su -
    
    rm -rf /etc/krb5.keytab
    
    adcli join domain-dns-name -U user -H hostname-fqdn
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    The user is a domain user with permissions to add machines to the domain. The hostname-fqdn is the host name in FQDN format for the machine.

    The -H option is necessary for adcli to generate SPN in the format of host/hostname-fqdn@REALM, which the Linux VDA requires.

  3. Verify system keytab.

    Run the sudo klist -ket command to ensure that the system keytab file has been created.

    Verify that the timestamp for each key matches the time the machine was joined to the domain.

  • If you use Samba to join the domain, complete the following steps:
  1. Install the package.

    sudo apt-get install samba krb5-user
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  2. Configure Samba.

    Open /etc/samba/smb.conf, and make the following settings:

    [global]

    workgroup = WORKGROUP

    security = ADS

    realm = REALM

    client signing = yes

    client use spnego = yes

    kerberos method = secrets and keytab

    WORKGROUP is the first field in REALM, and REALM is the Kerberos realm name in uppercase.

  3. Join the domain with Samba.

    Your domain controller must be reachable and you must have a Windows account with permissions to add computers to the domain.

    sudo net ads join <the Kerberos realm name in uppercase> -U <domain user with permission to add computers to the domain>
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Set up SSSD

Install or update required packages:

Install the required SSSD and configuration packages if not already installed:

sudo apt-get install sssd
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If the packages are already installed, an update is recommended:

sudo apt-get install --only-upgrade sssd
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Configure SSSD

SSSD configuration changes are required before starting the SSSD daemon. For some versions of SSSD, the /etc/sssd/sssd.conf configuration file is not installed by default and must be created manually. As root, either create or open /etc/sssd/sssd.conf and make the following settings:

[sssd]

services = nss, pam

config_file_version = 2

domains = domain-dns-name

[domain/domain-dns-name]

id_provider = ad

access_provider = ad

auth_provider = krb5

krb5_realm = REALM

# Set krb5_renewable_lifetime higher if TGT renew lifetime is longer than 14 days

krb5_renewable_lifetime = 14d

# Set krb5_renew_interval to lower value if TGT ticket lifetime is shorter than 2 hours

krb5_renew_interval = 1h

krb5_ccachedir = /tmp

krb5_ccname_template = FILE:%d/krb5cc_%U

# This ldap_id_mapping setting is also the default value

ldap_id_mapping = true

override_homedir = /home/%d/%u

default_shell = /bin/bash

ad_gpo_map_remote_interactive = +ctxhdx

Note:

ldap_id_mapping is set to true so that SSSD itself takes care of mapping Windows SIDs to Unix UIDs. Otherwise, Active Directory must be able to provide POSIX extensions. PAM service ctxhdx is added to ad_gpo_map_remote_interactive.

The domain-dns-name parameter in this context is the DNS domain name, such as example.com. The REALM is the Kerberos realm name in uppercase, such as EXAMPLE.COM. There is no requirement to configure the NetBIOS domain name.

For information about the configuration settings, see the man pages for sssd.conf and sssd-ad.

The SSSD daemon requires that the configuration file must have owner read permission only:

sudo chmod 0600 /etc/sssd/sssd.conf
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Start SSSD daemon

Run the following commands to start the SSSD daemon now and to enable the daemon to start upon machine startup:

sudo systemctl start sssd

sudo systemctl enable sssd
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PAM configuration

Run the following command and ensure that the SSS authentication and Create home directory on login options are selected:

sudo pam-auth-update
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Verify domain membership

The Delivery Controller requires that all VDA machines (Windows and Linux VDAs) have a computer object in Active Directory.

  • If you use adcli to verify domain membership, run the sudo adcli info domain-dns-name command to show the domain information.

  • If you use Samba to verify domain membership, run the sudo net ads testjoin command to verify that the machine is joined to a domain and the sudo net ads info command to verify extra domain and computer object information.

Verify Kerberos configuration

To verify that Kerberos is configured correctly for use with the Linux VDA, verify that the system keytab file has been created and contains valid keys:

sudo klist -ke
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This command displays the list of keys available for the various combinations of principal names and cipher suites. Run the Kerberos kinit command to authenticate the machine with the domain controller using these keys:

sudo kinit -k MACHINE\$@REALM
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The machine and realm names must be specified in uppercase. The dollar sign ($) must be escaped with a backslash (\) to prevent shell substitution. In some environments, the DNS domain name is different from the Kerberos realm name. Ensure that the realm name is used. If this command is successful, no output is displayed.

Verify that the TGT for the machine account has been cached using:

sudo klist
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Verify user authentication

SSSD does not provide a command-line tool for testing authentication directly with the daemon, and can only be done via PAM.

To verify that the SSSD PAM module is configured correctly, log on to the Linux VDA using a domain user account that has not been used before.

ssh localhost -l domain\\username

id -u

klist

exit
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Verify that the Kerberos tickets returned by the klist command are correct for that user and have not expired.

As a root user, verify that a corresponding ticket cache file was created for the uid returned by the previous id -u command:

ls /tmp/krb5cc_uid
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A similar test can be performed by logging on to KDE or Gnome Display Manager. Proceed to Step 6: Install the Linux VDA after the domain-joining verification.

PBIS

Download the required PBIS package

sudo wget https://github.com/BeyondTrust/pbis-open/releases/download/9.1.0/pbis-open-9.1.0.551.linux.x86_64.deb.sh
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Make the PBIS installation script executable

sudo chmod +x pbis-open-9.1.0.551.linux.x86_64.deb.sh
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Run the PBIS installation script

sudo sh pbis-open-9.1.0.551.linux.x86_64.deb.sh
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Join Windows domain

Your domain controller must be reachable and you must have an Active Directory user account with permissions to add computers to the domain:

sudo /opt/pbis/bin/domainjoin-cli join domain-name user
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The user is a domain user who has permissions to add computers to the Active Directory domain. The domain-name is the DNS name of the domain, for example, example.com.

Note: To set Bash as the default shell, run the sudo /opt/pbis/bin/config LoginShellTemplate/bin/bash command.

Verify domain membership

The Delivery Controller requires that all VDA machines (Windows and Linux VDAs) have a computer object in Active Directory. To verify that a PBIS-joined Linux machine is on the domain:

/opt/pbis/bin/domainjoin-cli query
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If the machine is joined to a domain, this command returns the information about the currently joined AD domain and OU. Otherwise, only the host name appears.

Verify user authentication

To verify that PBIS can authenticate domain users through PAM, log on to the Linux VDA using a domain user account that has not been used before.

sudo ssh localhost -l domain\\user

id -u
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Verify that a corresponding Kerberos credential cache file was created for the UID returned by the id -u command:

ls /tmp/krb5cc_uid
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Exit the session.

exit
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Proceed to Step 6: Install the Linux VDA after the domain-joining verification.

Step 4: Install .NET

In addition to the .NET Runtime, you must install .ASP.NET Core Runtime on all supported Linux distributions before you install or upgrade the Linux VDA. Version 6 is required for Amazon Linux 2. Version 8 is required for other distributions.

If your Linux distribution contains the .NET version that you require, install it from the built-in feed. Otherwise, install .NET from the Microsoft package feed. For more information, see https://docs.microsoft.com/en-us/dotnet/core/install/linux-package-managers.

After installing .NET, run the which dotnet command to find your runtime path.

Based on the command output, set the .NET runtime binary path. For example, if the command output is /aa/bb/dotnet, use /aa/bb as the .NET binary path.

Step 5: Download the Linux VDA package

  1. Go to the Citrix Virtual Apps and Desktops download page.
  2. Expand the appropriate version of Citrix Virtual Apps and Desktops.
  3. Expand Components to find the Linux VDA. For example:

    Components for Citrix Virtual Apps and Desktops

  4. Click the Linux VDA link to access the Linux VDA downloads.

    Linux VDA downloads

  5. Download the Linux VDA package that matches your Linux distribution.

  6. Download the GPG public key that you can use to verify the integrity of the Linux VDA package. For example:

    GPG public key

    To verify the integrity of the Linux VDA package, run the following commands to import the public key into the DEB database and to check the package integrity:

    sudo apt-get install dpkg-sig
    gpg --import <path to the public key>
    dpkg-sig --verify <path to the Linux VDA package>
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Step 6: Install the Linux VDA

Step 6a: Install the Linux VDA

Install the Linux VDA software using the Debian package manager:

For Debian 12.5:

sudo dpkg -i xendesktopvda_<version>.debian12_amd64.deb
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For Debian 11:

sudo dpkg -i xendesktopvda_<version>.debian11_amd64.deb
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Dependency list for Debian 12.5:

openjdk-17-jdk >= 17

imagemagick >= 8:6.9.11

ufw >= 0.36

desktop-base >= 12.0.6

libxrandr2 >= 2:1.5.2

libxtst6 >= 2:1.2.3

libxm4 >= 2.3.8

util-linux >= 2.38

gtk3-nocsd >= 3

bash >= 5.2

findutils >= 4.9.0

sed >= 4.9

cups >= 2.4

ghostscript >= 10.0.0~

libmspack0 >= 0.11

ibus >= 1.5

libgoogle-perftools4 >= 2.10~

libpython3.11 >= 3.11~

libsasl2-modules-gssapi-mit >= 2.1.~

libnss3-tools >= 2:3.87

libqt5widgets5 >= 5.15~

mutter >= 43.8

libqrencode4 >= 4.1.1

libimlib2 >= 1.10.0

libfuse2 >= 2.9.9

pulseaudio-utils >= 16.1
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Dependency list for Debian 11:

libnss3-tools >= 2:3.61

libfuse2 >= 2.9

openjdk-11-jdk >= 11

imagemagick >= 8:6.9.10

ufw >= 0.36

desktop-base >= 10.0.2

libxrandr2 >= 2:1.5.1

libxtst6 >= 2:1.2.3

libxm4 >= 2.3.8

util-linux >= 2.33

gtk3-nocsd >= 3

bash >= 5.0

findutils >= 4.6.0

sed >= 4.7

cups >= 2.2

ghostscript >= 9.53~

libmspack0 >= 0.10

ibus >= 1.5

libgoogle-perftools4 >= 2.7~

libpython3.9 >= 3.9~

libsasl2-modules-gssapi-mit >= 2.1.~

libqt5widgets5 >= 5.5~

mutter >= 3.38.6~

libqrencode4 >= 4.0.0

libimlib2 >= 1.5.1
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Note:

For a matrix of the Linux distributions and the Xorg versions that this version of the Linux VDA supports, see System requirements.

Step 6b: Upgrade the Linux VDA (optional)

The Linux VDA supports upgrades from the most recent version. For example, you can upgrade the Linux VDA from 2308 to 2311 and from 1912 LTSR to 2203 LTSR.

sudo dpkg -i <PATH>/<Linux VDA deb>

sudo apt-get install -f
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Note:

  • Upgrading an existing installation overwrites the configuration files under /etc/xdl. Before you conduct an upgrade, make sure to back up the files.

  • Starting with the 2407 release, the Linux VDA delegates package managers rpm or dpkg to handle configuration files during upgrades. The following describes how rpm and dpkg interact with changes to configuration files:

    • rpm: by default keeps the local version and saves the new version from the package with a .rpmnew extension.

    • dpkg: interactively prompts you with a choice on how to proceed. To silently upgrade the Linux VDA while retaining your local configuration file and saving the new package version as .dpkg-new or .dpkg-dist, use the following command:

       dpkg --force-confold -i package.deb  # Always keep your version, then save new package's version as *.dpkg-new or *.dpkg-dist
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Step 7: Install NVIDIA GRID drivers

Enabling HDX 3D Pro requires you to install the NVIDIA GRID drivers on your hypervisor and on the VDA machines.

To install and configure the NVIDIA GRID Virtual GPU Manager (the host driver) on the specific hypervisors, see the following guides:

To install and configure the NVIDIA GRID guest VM drivers, perform the following general steps:

  1. Ensure that the guest VM is shut down.
  2. In the hypervisor control panel, allocate a GPU to the VM.
  3. Start the VM.
  4. Install the guest VM driver on the VM.

Step 8: Configure the Linux VDA

Note:

Before setting up the runtime environment, ensure that the en_US.UTF-8 locale is installed on your OS. If the locale is not available on your OS, run the sudo locale-gen en_US.UTF-8 command. For Debian, edit the /etc/locale.gen file by uncommenting the # en_US.UTF-8 UTF-8 line and then run the sudo locale-gen command.

After installing the package, you must configure the Linux VDA by running the ctxsetup.sh script. Before making any changes, the script verifies the environment and ensures that all dependencies are installed. If necessary, you can rerun the script at any time to change settings.

You can run the script manually with prompting, or automatically with preconfigured responses. Review Help about the script before proceeding:

sudo /opt/Citrix/VDA/sbin/ctxsetup.sh --help
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Prompted configuration

Run a manual configuration with prompted questions:

sudo /opt/Citrix/VDA/sbin/ctxsetup.sh
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Automated configuration

For an automated install, the options required by the setup script can be provided with environment variables. If all required variables are present, the script does not prompt the user for any information, allowing for a scripted installation process.

Supported environment variables include:

  • CTX_XDL_NON_DOMAIN_JOINED=’y|n’ – Whether to join the machine to a domain. The default value is ‘n’. For domain-joined scenarios, set it to ‘n’.

  • CTX_XDL_AD_INTEGRATION=’winbind|sssd|centrify|pbis|quest’ – The Linux VDA requires Kerberos configuration settings to authenticate with the Delivery Controllers. The Kerberos configuration is determined from the installed and configured Active Directory integration tool on the system.

  • CTX_XDL_DDC_LIST=’<list-ddc-fqdns>‘ – The Linux VDA requires a space-separated list of Delivery Controller Fully Qualified Domain Names (FQDNs) to use for registering with a Delivery Controller. At least one FQDN or CNAME must be specified.

  • CTX_XDL_VDI_MODE=’y|n’ – Whether to configure the machine as a dedicated desktop delivery model (VDI) or hosted shared desktop delivery model. For HDX 3D Pro environments, set the value to ‘y’.

  • CTX_XDL_HDX_3D_PRO=’y|n’ – The Linux VDA supports HDX 3D Pro, a set of GPU acceleration technologies designed to optimize the virtualization of rich graphics applications. If HDX 3D Pro is selected, the VDA is configured for VDI desktops (single-session) mode - (that is, CTX_XDL_VDI_MODE=‘y’).

  • CTX_XDL_START_SERVICE=’y|n’ – Determines whether the Linux VDA services are started when the configuration is complete.

  • CTX_XDL_REGISTER_SERVICE=’y|n’ – The Linux Virtual Desktop services are started after machine startup.

  • CTX_XDL_ADD_FIREWALL_RULES=’y|n’ – The Linux VDA services require incoming network connections to be allowed through the system firewall. You can open the required ports (by default ports 80 and 1494) automatically in the system firewall for the Linux Virtual Desktop.

  • CTX_XDL_DESKTOP_ENVIRONMENT=gnome/gnome-classic/kde/mate/’<none>‘ – Specifies the GNOME, GNOME Classic, or MATE desktop environment to use in sessions. If you set it to ‘<none>‘, the default desktop configured on the VDA is used.

    You can also switch between desktop environments by running commands or using the system tray. For more information, see Desktop switching commands and System tray.

  • CTX_XDL_DOTNET_RUNTIME_PATH=path-to-install-dotnet-runtime – The path to install .NET for supporting the new broker agent service (ctxvda). The default path is ‘/usr/bin’.

  • CTX_XDL_VDA_PORT=port-number – The Linux VDA communicates with Delivery Controllers through a TCP/IP port.

  • CTX_XDL_SITE_NAME=<dns-name> – The Linux VDA discovers LDAP servers through DNS. To limit the DNS search results to a local Site, specify a DNS Site name. If unnecessary, set to ‘<none>‘.

  • CTX_XDL_LDAP_LIST=’<list-ldap-servers>‘ – The Linux VDA queries DNS to discover LDAP servers. If DNS cannot provide LDAP service records, you can provide a space-separated list of LDAP FQDNs with LDAP ports. For example, ad1.mycompany.com:389 ad2.mycompany.com:3268 ad3.mycompany.com:3268. To enable faster LDAP queries within an Active Directory forest, enable Global Catalog on a domain controller and specify the relevant LDAP port number as 3268. This variable is set to ‘<none>‘ by default.

  • CTX_XDL_SEARCH_BASE=search-base-set – The Linux VDA queries LDAP through a search base set to the root of the Active Directory Domain (for example, DC=mycompany,DC=com). To improve search performance, you can specify a search base (for example, OU=VDI,DC=mycompany,DC=com). If unnecessary, set to ‘<none>‘.

  • CTX_XDL_SUPPORT_DDC_AS_CNAME=’y|n’ – The Linux VDA supports specifying a Delivery Controller name using a DNS CNAME record.

Set the environment variable and run the configure script:

export CTX_XDL_NON_DOMAIN_JOINED='n'
export CTX_XDL_AD_INTEGRATION=sssd|winbind|centrify|pbis|quest
export CTX_XDL_DDC_LIST='<list-ddc-fqdns>'
export CTX_XDL_VDI_MODE='y|n'
export CTX_XDL_HDX_3D_PRO='y|n'
export CTX_XDL_START_SERVICE='y|n'
export CTX_XDL_REGISTER_SERVICE='y|n'
export CTX_XDL_ADD_FIREWALL_RULES='y|n'
export CTX_XDL_DESKTOP_ENVIRONMENT=gnome|gnome-classic|kde|mate|'<none>'
export CTX_XDL_DOTNET_RUNTIME_PATH='<path-to-install-dotnet-runtime>'
export CTX_XDL_VDA_PORT='<port-number>'
export CTX_XDL_SITE_NAME='<dns-site-name>'|'<none>'
export CTX_XDL_LDAP_LIST='<list-ldap-servers>'|'<none>'
export CTX_XDL_SEARCH_BASE='<search-base-set>'|'<none>'
export CTX_XDL_SUPPORT_DDC_AS_CNAME='y|n'
sudo -E /opt/Citrix/VDA/sbin/ctxsetup.sh --silent
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When running the sudo command, type the -E option to pass the existing environment variables to the new shell it creates. We recommend that you create a shell script file from the preceding commands with #!/bin/bash as the first line.

Alternatively, you can specify all parameters by using a single command:

sudo CTX_XDL_NON_DOMAIN_JOINED='n' \
CTX_XDL_AD_INTEGRATION=sssd|winbind|centrify|pbis|quest \
CTX_XDL_DDC_LIST='<list-ddc-fqdns>' \
CTX_XDL_VDI_MODE='y|n' \
CTX_XDL_HDX_3D_PRO='y|n' \
CTX_XDL_START_SERVICE='y|n' \
CTX_XDL_REGISTER_SERVICE='y|n' \
CTX_XDL_ADD_FIREWALL_RULES='y|n' \
CTX_XDL_DESKTOP_ENVIRONMENT=gnome|gnome-classic|kde|mate|'<none>' \
CTX_XDL_DOTNET_RUNTIME_PATH='<path-to-install-dotnet-runtime>' \
CTX_XDL_VDA_PORT='<port-number>' \
CTX_XDL_SITE_NAME='<dns-site-name>'|'<none>' \
CTX_XDL_LDAP_LIST='<list-ldap-servers>'|'<none>' \
CTX_XDL_SEARCH_BASE='<search-base-set>'|'<none>' \
CTX_XDL_SUPPORT_DDC_AS_CNAME='y|n' \
/opt/Citrix/VDA/sbin/ctxsetup.sh --silent
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Remove configuration changes

In some scenarios, you might have to remove the configuration changes made by the ctxsetup.sh script without uninstalling the Linux VDA package.

Review Help about this script before proceeding:

sudo /opt/Citrix/VDA/sbin/ctxcleanup.sh --help
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To remove configuration changes:

sudo /opt/Citrix/VDA/sbin/ctxcleanup.sh
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Important:

This script deletes all configuration data from the database and renders the Linux VDA inoperable.

Configuration logs

The ctxsetup.sh and ctxcleanup.sh scripts display errors on the console, with additional information written to the configuration log file /tmp/xdl.configure.log.

Restart the Linux VDA services to have the changes take effect.

Uninstall the Linux VDA software

To check whether the Linux VDA is installed and to view the version of the installed package:

dpkg -l xendesktopvda
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To view more detailed information:

apt-cache show xendesktopvda
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To uninstall the Linux VDA software:

dpkg -r xendesktopvda
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Note:

Uninstalling the Linux VDA software deletes the associated PostgreSQL and other configuration data. However, the PostgreSQL package and other dependent packages that were set up before the installation of the Linux VDA are not deleted.

Tip:

The information in this section does not cover the removal of dependent packages including PostgreSQL.

Step 9: Run XDPing

Run sudo /opt/Citrix/VDA/bin/xdping to check for common configuration issues with a Linux VDA environment. For more information, see XDPing.

Step 10: Run the Linux VDA

Once you have configured the Linux VDA using the ctxsetup.sh script, you use the following commands to control the Linux VDA.

Start the Linux VDA:

To start the Linux VDA services:

sudo systemctl start ctxhdx

sudo systemctl start ctxvda
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Stop the Linux VDA:

To stop the Linux VDA services:

sudo systemctl stop ctxvda

sudo systemctl stop ctxhdx
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Note:

Before you stop the ctxvda and ctxhdx services, run the systemctl stop ctxmonitord command to stop the monitor service daemon. Otherwise, the monitor service daemon restarts the services you stopped.

Restart the Linux VDA:

To restart the Linux VDA services:

sudo systemctl stop ctxvda

sudo systemctl restart ctxhdx

sudo systemctl restart ctxvda
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Check the Linux VDA status:

To check the running status of the Linux VDA services:

sudo systemctl status ctxvda

sudo systemctl status ctxhdx
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Step 11: Create machine catalogs

The process for creating machine catalogs and adding Linux VDA machines is similar to the traditional Windows VDA approach. For a more detailed description of how to complete these tasks, see Create machine catalogs and Manage machine catalogs.

For creating machine catalogs that contain Linux VDA machines, there are a few restrictions that differentiate the process from creating machine catalogs for Windows VDA machines:

  • For the operating system, select:
    • The Multi-session OS option for a hosted shared desktops delivery model.
    • The Single-session OS option for a VDI dedicated desktop delivery model.
  • Do not mix Linux and Windows VDA machines in the same machine catalog.

Note:

Early versions of Citrix Studio did not support the notion of a “Linux OS.” However, selecting the Windows Server OS or Server OS option implies an equivalent hosted shared desktops delivery model. Selecting the Windows Desktop OS or Desktop OS option implies a single user per machine delivery model.

Tip:

If you remove and rejoin a machine to the Active Directory domain, you must remove and add the machine to the machine catalog again.

Step 12: Create delivery groups

The process for creating a delivery group and adding machine catalogs containing Linux VDA machines is almost identical to Windows VDA machines. For a more detailed description of how to complete these tasks, see Create delivery groups.

For creating delivery groups that contain Linux VDA machine catalogs, the following restrictions apply:

  • Ensure that the AD users and groups that you select have been properly configured to log on to the Linux VDA machines.
  • Do not allow logon of unauthenticated (anonymous) users.
  • Do not mix the delivery group with machine catalogs that contain Windows machines.

For information about how to create machine catalogs and delivery groups, see Citrix Virtual Apps and Desktops 7 2407.

Install the Linux VDA on Debian manually