AIX Servers in LVS/DR and LVS/TUN Clusters

Introduction

In the AIX operating systems, ip addresses configured on the loopback interface will not participate the ARP protocol. Tested ok on AIX 6.1, sould works from AIX 5L

Disable ARP for VIP

Background : It is possible to disable arp on a real interface via noarp option. If a real interface is set up with arp on, you cannot add a inet alias on it whitout arp reply. The AIX "Virtual IP Address Interface" implementation allow you to add a virtual interface (not an alias) that is not arp-able

In LVS/DR clusters, we can disable ARP for VIP on AIX as follows:

smitty inet
select "Add de Virtual IP Address Interface"
under setup screen, specify,
address : 10.80.1.3 (dotted decimal)
netmask : 255.255.255.0 (match your real network) 
interface name : vi1 (or what you want)
activate interface : yes
interface to attach: lo0 (the real one, select the loopback ti disable arp)

Not real smit screens, it's a braindump... think ODM should be updated for persistence after reboot. it works like a charm in production environments (1 yr now) That's it.

--Baptiste Montarges 01:58, 11 April 2010 (CST)

References

• IBM documentation on Virtual Ethernet Interface on AIX