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Multi-homed NICs versus Virtual IPs

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Occasional Advisor

Multi-homed NICs versus Virtual IPs

There appears to be a lot of misuse of the terminology, but I will try to make myself understood.

I have an APA (AutoPort Aggregation) network environment on my HP-UX servers. Our Security Unit has requested that we no longer allow Service port (server to server) comnmunication for our applications and implement IP communication (server to switch) for the applications.

That would require slicing a NIC into dozens of IPs so the developers and testers can be sorted into application groups by unique hostname instead of assigning each developer and tester a unique service port.

Everyone seems to be using the same terminology for very different purposes.
APA is a "Multi-homing" product that "trunks" multiple physical NICs together into a load balancing and failover "Link Aggregate".
Some refer to this "trunk" as a Virtual NIC or IP (confusing).
The act of slicing a physical NIC into multiple virtual IPs is often refered to as "Multi-homing" as well (confusing).
These two processes appear to be sharing terminology, yet they are very different.
I tried and failed to slice an APA link aggregate (LA) into a second virtual NIC using ifconfig.
ifconfig lan900:1 [IP address] netmask [mask] up
It simply broke the network. I had to recycle the interface.
I tried and failed to configure additional LAs using the existing physical NICs that comprise lan900.
I tried using SAM and by editing /etc/rc.config.d/netconf
netconf doesn't seem to know anything about APA
Apparently, you can't reuse NICs for new LAs.

Is there any way to slice an APA LA into multiple virtual NICs?
Turgay Cavdar
Honored Contributor

Re: Multi-homed NICs versus Virtual IPs

>ifconfig lan900:1 [IP address] netmask [mask] up
>It simply broke the network. I had to recycle the interface.

Can you type here what is the command you are using, what are the command outputs? And what do you mean it broke the network?

Can you also send the output of:
# nwmgr --get -S apa

and conf files:
Occasional Advisor

Re: Multi-homed NICs versus Virtual IPs

ifconfig lan900:1 netmask up

The instant I hit the enter key for the above command, my terminal connection was severed. I didn't even get a carriage return.
I had to access the console and reset the lan900 interface using ifconfig.

I am unfamilar with "nwmgr". I have 18 HP-UX 11.11 and 11.23 servers. None of them have nwmgr. I assume this is an 11.31 utility.
I typically use lanscan -q:
900 0 1

Requested files attached as 7z archive
Mel Burslan
Honored Contributor

Re: Multi-homed NICs versus Virtual IPs

Functionality you want, i.e. slicing and dicing an APA interface into multiple virtual interfaces, is available starting v11.31, whereas the flavor of unix I hate the most, namely AIX, has this for years and years. Sorry to be the bearer of the bad news. Also, from anecdotal evidence I heard, the product is not as robust as one wants but this is hear-say, not my personal experience, so take it with a large grain of salt.
UNIX because I majored in cryptology...
Occasional Advisor

Re: Multi-homed NICs versus Virtual IPs

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