Linux Virtual Delivery Agent

Quick installation by using easy install (Recommended)

Important:

For fresh installations, we recommend you refer to this article for a quick installation. This article steps through how to install and configure the Linux VDA by using easy install. Easy install saves time and labor and is less error-prone than manual installation. It helps you set up a running environment of the Linux VDA by installing the necessary packages and customizing the configuration files automatically.

Supported distributions

  Winbind SSSD Centrify PBIS
RHEL 7.7 Yes Yes Yes Yes
RHEL 6.10 Yes Yes Yes No
CentOS 7.7 Yes Yes Yes Yes
CentOS 6.10 Yes Yes Yes No
Ubuntu 18.04 Yes Yes Yes Yes
Ubuntu 16.04 Yes Yes Yes Yes
SUSE 12.3 Yes No Yes No

Use easy install

To use this feature, do the following:

  1. Prepare configuration information and the Linux machine.
  2. Install the Linux VDA package.
    Go to the Citrix Virtual Apps and Desktops download page. Expand the appropriate version of Citrix Virtual Apps and Desktops. Click Components to download the Linux VDA package that matches your Linux distribution.
  3. Set up the runtime environment to complete the Linux VDA installation.

Step 1: Prepare configuration information and the Linux machine

Collect the following configuration information needed for easy install:

  • Host name - Host name of the machine on which the Linux VDA is to be installed
  • IP address of Domain Name Server
  • IP address or string name of NTP Server
  • Domain name - The NetBIOS name of the domain
  • Realm name - The Kerberos realm name
  • Fully Qualified Domain Name (FQDN) of the domain

Important:

  • To install the Linux VDA, verify that the repositories are added correctly on the Linux machine.
  • To launch a session, verify that the X Window system and desktop environments are installed.

Considerations

  • The workgroup name, by default, is the domain name. To customize the workgroup in your environment, do the following:

    a. Create the /tmp/ctxinstall.conf file on the Linux VDA machine.
    b. Add the workgroup=<your workgroup> line to the file and save your changes.

  • Centrify does not support pure IPv6 DNS configuration. At least one DNS server using IPv4 is required in /etc/resolv.conf for adclient to find AD services properly.

    Log:

     ADSITE   : Check that this machine's subnet is in a site known by AD   : Failed
              : This machine's subnet is not known by AD.
              : We guess you should be in the site Site1.
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    This issue is unique to Centrify and its configuration. To resolve this issue, do the following:

    a. Open Administrative Tools on the domain controller.
    b. Select Active Directory Sites and Services.
    c. Add a proper subnet address for Subnets.

  • Easy install supports pure IPv6 as of Linux VDA 7.16. The following preconditions and limitations apply:

    • Your Linux repository must be configured to ensure that your machine can download required packages over pure IPv6 networks.
    • Centrify is not supported on pure IPv6 networks.

    Note:

    If your network is pure IPv6 and all your input is in proper IPv6 format, the VDA registers with the Delivery Controller through IPv6. If your network has a hybrid IPv4 and IPv6 configuration, the type of the first DNS IP address determines whether IPv4 or IPv6 is used for registration.

  • If you choose Centrify as the method to join a domain, the ctxinstall.sh script requires the Centrify package. There are two ways for ctxinstall.sh to get the Centrify package:

  • If you choose PBIS as the method to join a domain, the ctxinstall.sh script requires the PBIS package. There are two ways for ctxinstall.sh to get the PBIS package:

Step 2: Prepare the hypervisor

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

Fix time synchronization on Citrix Hypervisor

When the Citrix Hypervisor Time Sync feature is enabled, within each paravirtualized Linux VM you experience issues with NTP and Citrix Hypervisor, both of which try to manage 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. No changes are required in HVM mode.

On some Linux distributions, if you are running a paravirtualized Linux kernel with Citrix VM Tools installed, you can check whether the Citrix Hypervisor 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

The Linux VMs with Hyper-V Linux Integration Services installed can apply the Hyper-V time synchronization feature to use the time of the host operating system. To ensure that the system clock remains accurate, you must enable this feature alongside the 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 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 of which 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: Install .NET Core Runtime as a prerequisite

Before installing the Linux VDA, install .NET Core Runtime according to the instructions at https://docs.microsoft.com/en-us/dotnet/core/install/linux-package-managers.

  • For the 1912 LTSR initial release, CU1, and CU2, Install .NET Core Runtime 2.1.
  • For CU3 and later releases, install .NET Core Runtime 3.1.

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

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

Step 4: Download the Linux VDA package

Go to the Citrix Virtual Apps and Desktops download page. Expand the appropriate version of Citrix Virtual Apps and Desktops and click Components to download the Linux VDA package that matches your Linux distribution.

Step 5: Install the Linux VDA package

To set up the environment for the Linux VDA, run the following commands.

For RHEL and CentOS distributions:

sudo yum  -y localinstall   <PATH>/<Linux VDA RPM>
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For Ubuntu distributions:

sudo dpkg -i <PATH>/<Linux VDA deb>
sudo apt-get install -f
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For SUSE distributions:

zypper -i install <PATH>/<Linux VDA RPM>
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Step 6: 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 7: Set up the runtime environment to complete the installation

Note:

Before setting up the runtime environment, ensure that the en_US.UTF-8 locale has been installed in your OS. If the locale is not available in your OS, run the sudo locale-gen en_US.UTF-8 command.

After installing the Linux VDA package, configure the running environment by using the ctxinstall.sh script. You can run the script in interactive mode or silent mode.

Note:

Easy install might seem unresponsive while it downloads .NET Core Runtime that is over 27 MB in size. Check /var/log/ctxinstall.log for the downloading progress.

To do a manual configuration, run the following command and type the relevant parameter at each prompt.

sudo /opt/Citrix/VDA/sbin/ctxinstall.sh
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Silent mode:

To use easy install in silent mode, set the following environment variables before running ctxinstall.sh.

  • CTX_EASYINSTALL_HOSTNAME=host-name – Denotes the host name of the Linux VDA server.
  • CTX_EASYINSTALL_DNS=ip-address-of-dns – IP address of DNS.
  • CTX_EASYINSTALL_NTPS=address-of-ntps – IP address or string name of the NTP server.
  • CTX_EASYINSTALL_DOMAIN=domain-name – The NetBIOS name of the domain.
  • CTX_EASYINSTALL_REALM=realm-name – The Kerberos realm name.
  • CTX_EASYINSTALL_FQDN=ad-fqdn-name
  • CTX_EASYINSTALL_ADINTEGRATIONWAY=winbind | sssd | centrify | pbis – Denotes the Active Directory integration method.
  • CTX_EASYINSTALL_USERNAME=domain-user-name – Denotes the name of the domain user; used to join the domain.
  • CTX_EASYINSTALL_PASSWORD=password – Specifies the password of the domain user; used to join the domain.

The ctxsetup.sh script uses the following variables:

  • CTX_XDL_SUPPORT_DDC_AS_CNAME=Y | N – The Linux VDA supports specifying a Delivery Controller name using a DNS CNAME record.
  • 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_VDA_PORT=port-number – The Linux VDA communicates with Delivery Controllers through a TCP/IP port.
  • CTX_XDL_REGISTER_SERVICE=Y | N – The Linux VDA 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 automatically open the required ports (by default ports 80 and 1494) in the system firewall for the Linux VDA.
  • 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_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_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. If unnecessary, set to <none>.
  • 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, it can be set to <none>.
  • CTX_XDL_FAS_LIST=’list-fas-servers’ – The Federated Authentication Service (FAS) servers are configured through AD Group Policy. The Linux VDA does not support AD Group Policy, but you can provide a semicolon-separated list of FAS servers instead. The sequence must be the same as configured in AD Group Policy. If any server address is removed, fill its blank with the <none> text string and do not modify the order of server addresses.
  • CTX_XDL_DOTNET_RUNTIME_PATH=path-to-install-dotnet-runtime – The path to install .NET Core Runtime for supporting the new broker agent service (ctxvda). The default path is /usr/bin.
  • CTX_XDL_START_SERVICE=Y | N – Whether or not the Linux VDA services are started when the configuration is complete.

If any parameters are not set, the installation rolls back to interactive mode, with a prompt for user input. When all parameters are already set through the environment variables, the ctxinstall.sh script still prompts for user input for the path to install .NET Core Runtime.

In silent mode, you must run the following commands to set environment variables and then run the ctxinstall.sh script.

export CTX_EASYINSTALL_HOSTNAME=host-name

export CTX_EASYINSTALL_DNS=ip-address-of-dns

export CTX_EASYINSTALL_NTPS=address-of-ntps

export CTX_EASYINSTALL_DOMAIN=domain-name

export CTX_EASYINSTALL_REALM=realm-name

export CTX_EASYINSTALL_FQDN=ad-fqdn-name

export CTX_EASYINSTALL_ADINTEGRATIONWAY=winbind | sssd | centrify | pbis

export CTX_EASYINSTALL_USERNAME=domain-user-name

export CTX_EASYINSTALL_PASSWORD=password

export CTX_XDL_SUPPORT_DDC_AS_CNAME=Y | N

export CTX_XDL_DDC_LIST='list-ddc-fqdns'

export CTX_XDL_VDA_PORT=port-number

export CTX_XDL_REGISTER_SERVICE=Y | N

export CTX_XDL_ADD_FIREWALL_RULES=Y | N

export CTX_XDL_HDX_3D_PRO=Y | N

export CTX_XDL_VDI_MODE=Y | N

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_FAS_LIST='list-fas-servers' | '<none>'

export CTX_XDL_DOTNET_RUNTIME_PATH=path-to-install-dotnet-runtime

export CTX_XDL_START_SERVICE=Y | N

sudo -E /opt/Citrix/VDA/sbin/ctxinstall.sh
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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_SUPPORT_DDC_AS_CNAME=Y|N \

CTX_XDL_DDC_LIST='list-ddc-fqdns' \

CTX_XDL_VDA_PORT=port-number \

CTX_XDL_REGISTER_SERVICE=Y|N \

CTX_XDL_ADD_FIREWALL_RULES=Y|N \

CTX_XDL_AD_INTEGRATION=1|2|3|4 \

CTX_XDL_HDX_3D_PRO=Y|N \

CTX_XDL_VDI_MODE=Y|N \

CTX_XDL_SITE_NAME=dns-name \

CTX_XDL_LDAP_LIST='list-ldap-servers' \

CTX_XDL_SEARCH_BASE=search-base-set \

CTX_XDL_FAS_LIST='list-fas-servers' \

CTX_XDL_DOTNET_RUNTIME_PATH=path-to-install-dotnet-runtime \

CTX_XDL_START_SERVICE=Y|N \

/opt/Citrix/VDA/sbin/ctxsetup.sh
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Step 8: Run XDPing

We provide a command-line utility, the Linux XDPing tool, to check for common configuration issues with a Linux VDA environment. You can install the XDPing package on any machine running a supported Linux distribution. XDPing does not require the Linux VDA package to be installed on the machine. For more information about the tool, see Knowledge Center article CTX202015.

Step 9: Run the Linux VDA

Start the Linux VDA:

To start the Linux VDA services:

sudo /sbin/service ctxhdx start

sudo /sbin/service ctxvda start
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Stop the Linux VDA:

To stop the Linux VDA services:

sudo /sbin/service ctxvda stop

sudo /sbin/service ctxhdx stop
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Note:

Before you stop the ctxvda and ctxhdx services, run the service ctxmonitorservice stop 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 /sbin/service ctxvda stop

sudo /sbin/service ctxhdx restart

sudo /sbin/service ctxvda start
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Check the status of the Linux VDA:

To check the running status of the Linux VDA services:

sudo /sbin/service ctxvda status

sudo /sbin/service ctxhdx status
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Step 10: Create the machine catalog in Citrix Virtual Apps or Citrix Virtual Desktops

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 11: Create the delivery group in Citrix Virtual Apps or Citrix Virtual Desktops

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 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.

Important:

Publishing applications is supported with Linux VDA Version 1.4 and later. However, the Linux VDA does not support the delivery of desktops and apps to the same machine.

For information about how to create machine catalogs and delivery groups, see Citrix Virtual Apps and Desktops 7 1912 LTSR.

Troubleshooting

Use the information in this section to troubleshoot issues that can arise from using this feature.

Joining a domain by using SSSD fails

An error might occur when you attempt to join a domain, with the output similar to the following (verify logs for screen printing):

Step 6: join Domain!Enter ctxadmin's password:Failed to join domain: failed to lookup DC info for domain 'CITRIXLAB.LOCAL' over rpc: The network name cannot be found

/var/log/xdl/vda.log:

2016-11-04 02:11:52.317 [INFO ] - The Citrix Desktop Service successfully obtained the following list of 1 delivery controller(s) with which to register: 'CTXDDC.citrixlab.local (10.158.139.214)'.
2016-11-04 02:11:52.362 [ERROR] - RegistrationManager.AttemptRegistrationWithSingleDdc: Failed to register with http://CTXDDC.citrixlab.local:80/Citrix/CdsController/IRegistrar. Error: General security error (An error occurred in trying to obtain a TGT: Client not found in Kerberos database (6))
2016-11-04 02:11:52.362 [ERROR] - The Citrix Desktop Service cannot connect to the delivery controller 'http://CTXDDC.citrixlab.local:80/Citrix/CdsController/IRegistrar' (IP Address '10.158.139.214')
Check the following:- The system clock is in sync between this machine and the delivery controller.
-  The Active Directory provider (e.g. winbind daemon) service is running and correctly configured.
-  Kerberos is correctly configured on this machine.
If the problem persists, please refer to Citrix Knowledge Base article CTX117248 for further information.
Error Details:
Exception 'General security error (An error occurred in trying to obtain a TGT: Client not found in Kerberos database (6))' of type 'class javax.xml.ws.soap.SOAPFaultException'.
2016-11-04 02:11:52.362 [INFO ] - RegistrationManager.AttemptRegistrationWithSingleDdc: The current time for this VDA is Fri Nov 04 02:11:52 EDT 2016.
Ensure that the system clock is in sync between this machine and the delivery controller.
Verify the NTP daemon is running on this machine and is correctly configured.
2016-11-04 02:11:52.364 [ERROR] - Could not register with any controllers. Waiting to try again in 120000 ms. Multi-forest - false
2016-11-04 02:11:52.365 [INFO ] - The Citrix Desktop Service failed to register with any controllers in the last 470 minutes.
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/var/log/messages:

Nov 4 02:15:27 RH-WS-68 [sssd[ldap_child[14867]]]: Failed to initialize credentials using keytab [MEMORY:/etc/krb5.keytab]: Client 'RH-WS-68$@CITRIXLAB.LOCAL' not found in Kerberos database. Unable to create GSSAPI-encrypted LDAP connection.Nov 4 02:15:27 RH-WS-68 [sssd[ldap_child[14867]]]: Client 'RH-WS-68$@CITRIXLAB.LOCAL' not found in Kerberos database

To resolve this issue:

  1. Run the rm -f /etc/krb5.keytab command.
  2. Run the net ads leave $REALM -U $domain-administrator command.
  3. Remove the machine catalog and delivery group on the Delivery Controller.
  4. Run /opt/Citrix/VDA/sbin/ctxinstall.sh.
  5. Create the machine catalog and delivery group on the Delivery Controller.

Ubuntu desktop sessions show a gray screen

This issue occurs when you launch a session that is then blocked in a blank desktop. In addition, the console of the machine also shows a gray screen when you log on by using a local user account.

To resolve this issue:

  1. Run the sudo apt-get update command.
  2. Run the sudo apt-get install unity lightdm command.
  3. Add the following line to /etc/lightdm/lightdm.conf:
    greeter-show-manual-login=true

Attempts to launch Ubuntu desktop sessions fail due to a missing home directory

/var/log/xdl/hdx.log:

2016-11-02 13:21:19.015 <P22492:S1> citrix-ctxlogin: StartUserSession: failed to change to directory(/home/CITRIXLAB/ctxadmin) errno(2)

2016-11-02 13:21:19.017 <P22227> citrix-ctxhdx: logSessionEvent: Session started for user ctxadmin.

2016-11-02 13:21:19.023 <P22492:S1> citrix-ctxlogin: ChildPipeCallback: Login Process died: normal.

2016-11-02 13:21:59.217 <P22449:S1> citrix-ctxgfx: main: Exiting normally.
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Tip:

The root cause of this issue is that the home directory is not created for the domain administrator.

To resolve this issue:

  1. From a command line, type pam-auth-update.

  2. In the resulting dialog, verify that Create home directory login is selected.

    Image of Ubuntu cannot launch session

Session does not launch or ends quickly with dbus error

/var/log/messages (for RHEL or CentOS):

Oct 27 04:17:16 CentOS7 citrix-ctxhdx[8978]: Session started for user CITRIXLAB\ctxadmin.

Oct 27 04:17:18 CentOS7 kernel: traps: gnome-session[19146] trap int3 ip:7f89b3bde8d3 sp:7fff8c3409d0 error:0

Oct 27 04:17:18 CentOS7 gnome-session[19146]: ERROR: Failed to connect to system bus: Exhausted all available authentication mechanisms (tried: EXTERNAL, DBUS_COOKIE_SHA1, ANONYMOUS) (available: EXTERNAL, DBUS_COOKIE_SHA1, ANONYMOUS)#012aborting...

Oct 27 04:17:18 CentOS7 gnome-session: gnome-session[19146]: ERROR: Failed to connect to system bus: Exhausted all available authentication mechanisms (tried: EXTERNAL, DBUS_COOKIE_SHA1, ANONYMOUS) (available: EXTERNAL, DBUS_COOKIE_SHA1, ANONYMOUS)

Oct 27 04:17:18 CentOS7 gnome-session: aborting...

Oct 27 04:17:18 CentOS7 citrix-ctxgfx[18981]: Exiting normally.

Oct 27 04:17:18 CentOS7 citrix-ctxhdx[8978]: Session stopped for user CITRIXLAB\ctxadmin.
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Or, alternately for Ubuntu distributions, use the log /var/log/syslog:

Nov  3 11:03:52 user01-HVM-domU pulseaudio[25326]: [pulseaudio] pid.c: Stale PID file, overwriting.

Nov  3 11:03:52 user01-HVM-domU pulseaudio[25326]: [pulseaudio] bluez5-util.c: Failed to get D-Bus connection: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.

Nov  3 11:03:52 user01-HVM-domU pulseaudio[25326]: [pulseaudio] hashmap.c: Assertion 'h' failed at pulsecore/hashmap.c:116, function pa_hashmap_free(). Aborting.

Nov  3 11:03:52 user01-HVM-domU pulseaudio[25352]: [pulseaudio] core-util.c: Failed to connect to system bus: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.

Nov  3 11:03:52 user01-HVM-domU pulseaudio[25352]: message repeated 10 times: [ [pulseaudio] core-util.c: Failed to connect to system bus: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.]

Nov  3 11:03:52 user01-HVM-domU pulseaudio[25352]: [pulseaudio] pid.c: Daemon already running.Nov  3 11:03:58 user01-HVM-domU citrix-ctxgfx[24693]: Exiting normally
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Some groups or modules do not take effect until a restart. If the dbus error messages appear in the log, we recommend that you restart the system and retry.

SELinux prevents SSHD from accessing the home directory

The user can launch a session but cannot log on.

/var/log/ctxinstall.log:

Jan 25 23:30:31 yz-rhel72-1 setroubleshoot[3945]: SELinux is preventing /usr/sbin/sshd from setattr access on the directory /root. For complete SELinux messages. run sealert -l 32f52c1f-8ff9-4566-a698-963a79f16b81

Jan 25 23:30:31 yz-rhel72-1 python[3945]: SELinux is preventing /usr/sbin/sshd from setattr access on the directory /root.

*****  Plugin catchall_boolean (89.3 confidence) suggests   ******************

If you want to allow polyinstantiation to enabled

   Then you must tell SELinux about this by enabling the 'polyinstantiation_enabled' boolean.

You can read 'None' man page for more details.

    Do

       setsebool -P polyinstantiation_enabled 1

*****  Plugin catchall (11.6 confidence) suggests   **************************

If you believe that sshd should be allowed setattr access on the root directory by default.

Then you should report this as a bug.

You can generate a local policy module to allow this access.

      Do

       allow this access for now by executing:

       # grep sshd /var/log/audit/audit.log | audit2allow -M mypol

# semodule -i mypol.pp
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To resolve this issue:

  1. Disable SELinux by making the following change to /etc/selinux/config.

    SELINUX=disabled

  2. Restart the VDA.