topic Re: Bonding and virtual Ips in Operating System - Linux

Bonding and virtual Ips

Sac_3 — Fri, 21 Mar 2008 20:00:15 GMT

Hi All,

I am suppose to configure bonding on one of our linux servers running Red Hat Enterprise Linux AS release 4 (Nahant Update 3) version.

Im suppose to bond eth0 and eth2 interface.
eth1 is assigned 3.xx.xx.xx ip. Now, i have one Question/need clarification here before i proceed with configuring bonding. I see that there are some virtual ips configured on eth0 interface i.e eth0:1 eth0:2...eth0:6.

Now if i configure bonding, will the virtual interface would be effected....?If so, do i need to re-configure the virtual ip's as bond0:1 bond0:2...bond0:6..?

Pls suggest

Regards,
SaC

Re: Bonding and virtual Ips

Kevin Wright — Fri, 21 Mar 2008 21:33:56 GMT

configure bond0,bond0:1, bond0:2 etc

Re: Bonding and virtual Ips

Sac_3 — Fri, 21 Mar 2008 21:51:56 GMT

Kewl! Thats what i thought!

Thx for confirming

Regards,
SaC

Re: Bonding and virtual Ips

VKVM — Sat, 22 Mar 2008 16:22:19 GMT

Just some notes/observations about bonding (you already have the answer regarding interface names).

Firstly, I'm assuming you're using the same driver for eth0 and eth2.

I'm using RHEL 4u5 which fixes some issues we ran into with prior releases. Bonding has been a pain since we started using it in RHEL 3. We've used in primarily in an active-backup mode with ARP monitoring. mii-monitoring tends to be simpler to maintain.

- ARP monitoring can have some weird interactions with routing in Linux. Occasionally bringing an unrelated interface (e.g. eth3) down/up multiple times will cause the wrong interface to be used for routing traffic over the bond. It's rare, but it can happen. Most people will not encounter this. I don't think this is fixed in any current RHEL version and I don't think this is RHEL specific.

- NIC ordering can get screwed up if you crash the system (e.g. simulate with sysrq-b) which in turn can kill your bond on reboot. I believe this is fixed via newer hotplug and init scripts in current RHEL versions.

- you may run into some probs with the bond coming up before some of the slave interfaces are configured correctly. I can't remember the details (it's been a while) but it may have been fixed by Redhat in current releases. Workaround is to rename ifcfg-bond0 to something that sorts last alphabetically (e.g. ifcfg-zbond0)

Since you're on RHEL 4u3, I would suggest you upgrade to update 5 or 6 as they have a lot of bug fixes.

I assume if bonding is new to your environment that you are testing in a non-production environment, making this more feasible.

If not, upgrading may cause other issues, so take it slow 8-)

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VK