Nic Redundancy

[Liadi]

Hello all.
I got 4 nic Ethernet Card (A5506B) over HP-UX B.11.00 9000/800. I want it to have 2 ports with same ip and to be redundent. Any suggestions on how doing it?

[Rajeev Shukla · Accepted solution]

Hi,
Few rules.
Rule 1. You can not have same IP address for NIC cards at the same time. What you can do is
a)configure them but keep it down using,
ifconfig lan1 down
and as soon as lan0 goes down you can bring up lan1
b) Buy other products like MC/SG
c) Write you'r own script which configures the 2nd lan card as soon as first goes down.
Rule 2. You can not have 2 NIC cards on the same network

[Liadi]

First thanks for the quick response.

I don't have 2 cards, I have one card with 4 nics. isn't there any way to configure 2 (or more) of them in such a way that if one is down the other goes up with same ip?

[Bernhard Mueller]

Hi,

Rajeev has said the most important things.

Alternatively you may consider using APA (Auto Port Aggregation) which allows failover and trunking of network ports, but this requires a license while you could write a monitoring/failover script on your own.

Regards,
Bernhard

[Neil Steurs]

Get APA (Auto Port Aggregation) - this is exactly what its for.

It needs a license, but I don't think its a lot of money compared to what it can do. And if you connect the cards through different switches, you have even more resilience and the network guys can do maintenance without affecting your server connectivity.

Its quite easy to set up too.

[Bill Hassell]

Very important for APA: your swicth *must* support duplicate IP's on different interfaces. APA works with the switch to not only provide a failover path but to load balance for higher throughput. You can read all about APA at http://docs.hp.com (look for the keyword aggregation.

[PVR]

Hi bill ,

I think APA software part will take care of Ip and all ip (even MAC address) related communication. It has nothing to do with switch / hub. I mean no special criteria for selecting the switch.

It is true that for better redundancy, switch has to provide a failover path.

Pl revert back if am wrong...

[Bill Hassell]

APA can be configured to operate in LAN Monitor mode with anyu hub or switch. However there won't be any load balancing or parallel data channels. For that, support for Cisco's proprietary Fast EtherChannel (FEC/PAgP) technology or IEEE 802.3ad link aggregation control protocol (LACP) is required. Switches with this feature can provide load balancing as well as duplicate switch paths (two switches provide redundancy as well as load balancing).