Dual Network Cards on Cloverleaf Server?

[Victor Ligenza]

Does anyone have any experience or insight they could share?

We are in the planning process of re IP’ing our entire network  😯 .  The question was asked that if a second network card was installed on our cloverleaf AIX box  😕 .  We could then potentially use two IP addresses for the interface connections.  This would allow us to use a phased in approach and reconfigure new IP addresses one connection at a time over a period of days.  

I’m not sure if there will be a license key impact of this either.

TIA.

Topic

[Michael Hertel]

We have two hosts with 2 nics on each of our boxes.

We have 6 ip addresses, one for each card and two

floating addresses.

One floating address points to ie-test-if and the other one points to ie-prod-if.

The unix admins move the two ip addresses between the boxes depending on which box is test and which one is prod. Occassionally we will have both floaters on the same box.

[Russ Ross]

My expereince is that inbound traffic to cloverleaf on 2 different IPs/NICs works just fine.

However, outbound traffic from cloverleaf using 2 different IPs/NICs presents a problem especially if firewalls are invloved.

The outbound traffic from the cloverleaf AIX server in my experience always ends up using the IP/NIC that the default gateway is assigned to (“netstat -rn” and “netstat -in” are commands I’ve used to see the IP/NIC mappings).

I have accomplished what you are describing by dividing the AIX server into LPARs and each of the LPARs has its own IP.

I would like to point out that the cloverleaf license key is tied to the physical host ID displayed by running hcihostid which is the same for all LPARs on the same physical AIX server.

In other words one cloverleaf license will run as many LPARs as you have resources for on one physical AIX server.

I have also been able to tie multiple NIC cards together to one IP address using ehter-channel which isn’t what you want to do but is worth knowing about as a way to load balance traffic across multiple NICs that share one common IP.

Russ Ross
RussRoss318@gmail.com

[Victor Ligenza]

Thank you both for the great information.  

We have successfully implemented using a second NIC with the new IP scheme and are using it for one application.  Now we can continue on with our re-IP project in a more modular fashion.

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