Route Table

What is the issue you're trying to address? Do you want LTM to not answer ARP requests for the self IP addresses?

 

 

Aaron

We are trying to migrate the old pair to a new one but keep all of the configuration in tact. The new pair already have other productions configurations on them .

 

We assigned 2 ports on each one of the new ones to be given for the old boxes configurations and we kept the ports on new F5s side as well as the switch side then. However; after we created the Self IPs for the newely assigned ports we got reports from the storage team that thier backups are failing. Then during the troubleshooting process we discovered that the back up device is behind the new F5 with its default gateway being on of the self IPs of the new F5. The node behind the new F5 was trying to talk to another node behind the old F5 but since the new F5 is built with the Self IPs of the old F5 the new F5 was trying to route the traffic out to the node behind the old F5 out of its disabled port.

 

We verified that the route table inculdes an entry for a self IP which is assigned to a port that is disabled

Irrespective of service port configuration, the ARP response from the new unit is what would break the requests to the old unit. I don't think you can expect two hosts with the same IP address(es) to work. You cannot disable ARP on the self IP address. The simplest fix might be to assign one of the LTM's a new set of self IP addresses. Once the old unit is decommissioned, you could either add or replace the self IP's on the new unit with the old unit's addresses.

 

 

Aaron

So we can create the VIPs,Pools and Nodes of the old LTM on to the new one with the same IP addresses for VIPs and nodes then on decom day we can create the Self IPs on the new LTM and enable the ports.. right?

If the new unit doesn't have any switch ports enabled, that would work. It would be safer to leave the cables unplugged though if the VIP and self IP addresses are the same between the old and new units.

 

 

Aaron

New unit is already in production and have other VIPs on them but not part of the old units. Is it going to work?