LAN failover without MC/SG

[Ley Youn Wai]

Is there a way to switch the LAN interface on the same hostname without using MC/SG?

[Patrick Wallek]

Check out Auto Port Aggregation software.

http://www.software.hp.com/cgi-bin/swdepot_parser.cgi/cgi/displayProductInfo.pl?productNumber=J4240AA

This should do what you want to do, although it appears it is only available for HP-UX 11.X.

[Ley Youn Wai]

Can this be implemented without installing any new product?

[Patrick Wallek]

I don't think so. APA is a purchaseable product. I think the pricing on the web page said that it was about $1100US.

I don't know that you can automatically do what you want without APA or MC/SG.

[rick jones]

indeed APA is an add-on item for which you need to pay.

if you are adept enough with scripting and understand the issues well enough, you could concoct some scripts that run via cron/at or something that try somehow to determine the health of a given NIC and then move its IP address(es) to a backup NIC when the original one appears to fail.

it will not offer the load-balancing of APA, and will probably not detect and compensate for link failures as quickly, but if you really are strapped for money it should be possible.

still, i would really suggest you spend the money on APA. i suspect it will be a more complete solution, and one for which you can get HP support should something go awry.

[Enrico Venturi]

Forget about APA: it's only another HP commercial solution money expensive and inadequate for your needs.
APA allows to have one IP to many MAC addresses, but it requires additional HW and SW.
There are several solutions for your "problem", and they depend on the stack (IP, OSI, .... ) you need to make redundant against lancard failover.
You have two lancards, ok?
lan0 is the main, lan1 is the spare; at the system boot you must configure lan0, and leave lan1 not configured.
Basically you need a script (started at system boot) which periodically check for the lan card working status; if/when lan0 fails the script must unconfigure lan0 and configure lan1; if/when lan1 fails the script must performe the opposite action.
This provide to have the IP mapped (in different time slots) on two different lan cards.
If you need to make OSI redundant, then you can configure two subnets on lan0 and lan1, having the same NSAP and the parameter snet_query_subnet = 1: this fact guarantees that output PDU's are sent over the first lan card available ... if the first isn't available the PDU is sent over the second, and so on.
If you need to make another stack (proprietary for example...) redundant, then, if the stack is started by command line, you can detect the lan card failure by the script used for IP, the you can kill the running stack and start the new one on the new running lan card (after having configured it)
Hope this help you

Ciao

[Ley Youn Wai]

Thanks for the info.

I'm not very good at scripting and do not have time to write one from scratch. If you have a sample script that I can use to modify, please email to me at youn-wai_ley@hp.com