DHCP client behavior with Layer 3 routing image

Up until now Brocade devices supported the DHCP client IP address discovery and auto-update feature on out-of-band interfaces, physical interface ports part of default and non-default VLANs.

Brocade ICX devices acting as DHCP clients obtain a dynamic IP address from the DHCP server which are in the same subnet or in different subnets. If the device acts as a Layer 2 switch, then the device assigns the dynamic IP address to the ICX Layer 2 switch. The set of server racks connected downstream to the ICX device also receive the IP address from the same DHCP server.

Network management tool and DHCP servers are able to communicate to the ICX and server racks downstream to ICX with this newly acquired IP address, through a set of in-band interface ports, which belong to the default VLAN. After migrating to the Layer 3 router version of the Brocade Fastiron operating system some manageability and reachability issues were lost. These issues are now resolved in the Layer 3 routing image and the same level of auto-provisioning will be provided on router systems.

The following enhancements solve the manageability and reachability issues:

  • The ICX device is managed even during cable movement from one in-band interface port to another.
  • Servers which are connected downstream to ICX are managed.
  • Using DHCP, acquiring IP or upgrade configuration is zero-touch.
  • By default, the device allows traffic to pass (reachability) across all ports.
  • All ICX devices will support DHCP client on default virtual interfaces port. Hence the client will obtain the dynamic IP address through the VE interface.
  • When the ICX boots up in factory default mode running the Layer 3 router image, the default VE gets created automatically and participates in switching between all the interface ports. This creates a meshed network to manage the ICX and downstream servers.

High availability considerations

Stacking - After switchover between active and standby devices, the DHCP process re-acquires IP addresses and follows the upgrade process.

Campus Fabric (SPX) - The DHCP client is able to send packets through all CB and PE ports. PE ports can be members of the VE. However, only the default VE can be a DHCP client.

Configuration considerations

  • To create a default VE interface port, the upstream interface port from the ICX device must
    should, or must?
    be part of the default VLAN.
  • If the upstream interface port is part of a user VLAN or Out of Band interface port, the default VE interface will not be created.

Upgrade considerations

When upgrading from FastIron 08.0.60 or previous releases to FastIron 08.0.61, if rules to create default VE are met, the following occur automatically: the default VE is created, the DHCP client is enabled, and it acquires the IP address.

What is "it"? Does the VE acquire the IP address, or the DHCP client?

Parent topic: DHCP Clients