NetScaler SD-WAN introduces the ability to use Standard or Enterprise Edition appliances as either DHCP Servers or DHCP Relay agents. You can configure your appliance to issue IP addresses using DHCP or forward DHCP packets between clients and servers.
NetScaler SD-WAN appliances can be configured as DHCP server that assigns and manages IP addresses from specified address pools within the network to DHCP clients. The DHCP server can be configured to assign additional parameters such as the IP address of the Domain Name System (DNS) server and the default router. DHCP server accepts address assignment requests and renewals. The DHCP server also accepts broadcasts from locally attached LAN segments or from DHCP requests that have been forwarded by other DHCP relay agents within the network.
To enable DHCP server:
1. Navigate to Configuration → Appliance Settings → Network Adapters. In the Network Adapters page, look for the Management Interface DHCP Server pane.
2. Click the Enable DHCP Server checkbox to start the server, then enter the Lease Time (in minutes), the Domain Name, and define the IP Address range by entering a Start IP Address and an End IP Address.
3. Click the Change Settings button to finish configuring the DHCP Server.
4. Click Show Client to view the current DHCP clients, and click Clear Clients to release the DHCP Client leases.
A DHCP relay agent is a host or router that forwards DHCP packets between clients and servers. Network administrators can use the DHCP Relay service on the management port of the SD-WAN (Standard or Enterprise Editions) appliances to relay requests and replies between local DHCP Clients and a remote DHCP Server. This allows local hosts to acquire dynamic IP addresses from the remote DHCP Server. Relay agent receives DHCP messages and generates a new DHCP message to send out on another interface.
To enable DHCP relay service:
1. Navigate to Configuration → Appliance Settings → Network Adapters. In the Network Adapters page, look for the Management Interface DHCP Relay pane.
2. Click the Enable DHCP Relay checkbox to enable the service. Enter the DHCP Server IP Address and click the Change Settings button to begin using your appliance as a DHCP Relay Agent.
The runtime Virtual IP address, Subnet Mask, and Gateway settings are logged and archived in a log file called “CBVW_ip_learned.log”. Events are generated when Dynamic Virtual IPs are learned, released, or expired, and when there is a communication issue with the learned Gateway or DHCP server; or when duplicate IP addresses are detected in the archived log file. If duplicate IPs are detected at a site, Dynamic Virtual IP addresses are released and renewed until all Virtual Interfaces at the site obtain unique Virtual IP addresses.
To monitor DHCP client WAN links:
1. In the Virtual WAN→ Enable/Disable/Purge Flows page, the DHCP Client WAN Links table provides the status of learned IPs.
2. You can request to renew the IP, which refreshes the lease time. You can also choose to Release Renew, which will issue a new IP address with a new lease.