Redundant network cards

[Mark Eisenhardt]

I've been asked if it's possible to configure a hot spare nic card, both having the same IP but only 1 is active. In case of a failure the other one would pickup the traffic. (HP-UX 11.x)
Does anyone know if this can be accomplished, or if HP has software that will allow this type of configuration?
Thanks

[John Poff]

Hi,

You might be able to script up something to do it for you, but it will be tricky.

MC/ServiceGuard has this capability built in. Probably if you need instant failover of your LAN cards you will need failover if your machine fails also. I'd suggest looking at MC/SG and putting your application into a cluster.

JP

[harry d brown jr · Accepted solution]

Look into APA:

http://docs.hp.com/hpux/onlinedocs/J4240-90016/00/00/1-con.html

Funny thing though, I can't remember thee last time I actually had a network card failure on any of our 600+ servers!

live free or die
harry

[Mark Eisenhardt]

It's not really for a card failure, they are configuring redundant network switches. So if they need to take 1 down for maintenance it would not interupt the user traffic.
Hence thats why this was asked of me.
Thanks

[Mark Eisenhardt]

Thanks Harry I'm checking out APA now. It appears that this may be what I'll need.

[John Poff]

Hi,

Harry is right. Auto Port Aggravation is probably the way to go. It is a real pain to setup and get going, but once you have it working it is great. I'm not sure if you can aggregate two or more cards to separate switches, but it is probably the closest thing to what you are looking for.

JP

[avsrini]

Hi Mark,
As per my knowledge, you cant have APA on different switches. Because when you use APA, 2 or more Physical ports are aggegated as a single logical port. Which is like a single port on a single switch. You can't have half port on switch and half on other one.

You can use APA for load balancing and port failure.
If you need for switch failure's, then you have to go for MC Service Guard only.

Srini.

[Steven E. Protter]

I did not know you could do port agregation with two seperate NIC cards. I thought you needed a multi-port NIC card.

Can someone clarify for me? Can I take the two NIC's in my rp5450 server and do port agregation(assuming I purchase the softwre from HP)?

This post is kind of interesting, as my supervisor wants to know about it. At a Monday meeting.

[rick jones]

Indeed, one can use multiple, single-port NICs with Auto Port Aggregation (APA).

Also, it is (iirc) possible to use APA with multiple switches. The limitation is that only links to one switch can be "active" the links to the other switch have to be standby - the APA software does not do the "meshing" support that would be required to go active/active across multiple switches.

[Jeff Carver]

I would like more details on what was mentioned as "It is a real pain to setup and get going, but once you have it working it is great." and what suggestions anyone might have regarding how to make APA easier to setup.

[John Poff]

Hi Jeff,

I made the comment you referred to.

We've tried installing APA twice here. The first time we were successful but it took an entire day. The second time took all day also but was a failure and we haven't attempted it again. APA is a nice product once you have it running correctly, but getting there can be quite an adventure. First, you have to get the network cards you are going to use all setup exactly right. Exactly. Speed, duplex, everything. Then, you install APA and the patches it needs. Then, your local network wizard has to setup the port on the switch side to do the aggregation [I think Cisco, which we have, calls it 'trunking']. Then, you have to have a good understanding of APA and the config files, and you have to get the config setup for aggregating the cards like you want them. Otherwise, APA will grab what it wants and run with it. THen, you start APA and hope for the best.

I was here for the first try, and we ran across a bad LAN card in one box which made things tougher. Unfortunately, the bad card wasn't very obvious, and we weren't even sure of it until we had it replaced. After we got it running [on two boxes], it worked great and we didn't have any problems except when our local LAN wizard messed with the port on the switch. I didn't drive this first installation. We had a consultant in to do it. This guy is very sharp and has lots of HP and Unix experience, but he hadn't done an APA install before. With all his skill and knowledge we managed to complete it in a long day. Without his help I'm pretty sure I wouldn't have gotten it going [at that time anyway - over three years ago].

I wasn't here for the second try, and the two guys that were here for it spent around 16 hours trying to get it going before they had to give up.

APA is a nice product, but unlike a lot of other HP products, you really need to have a good understanding of how it works, how to install it, and how to configure it. Everything has to come together in a certain order to make it work. We originally did it with 100 Mb cards and it ran great. Now, with all the 1 Gb LAN cards we just don't have the traffic to justify the hassle of installing it, yet. However, once you have it working, it is slick. You can drop out a LAN card and APA doesn't blink an eye. You just keep running with a smaller aggregate pipe. It's even slicker than the LAN failovers in MC/SG because you don't change LAN devices and so you don't lose any connections.

Now maybe you'll understand why I refer to it as:

Auto Port *Aggravation* ;)

JP