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[SOLVED] Add a third NIC the "SME way"

Offline DanB35

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[SOLVED] Add a third NIC the "SME way"
« on: January 07, 2016, 03:58:31 PM »
I thought I'd seen a wiki page on this, but Google isn't finding it, so...

I'm running a SME 9.1 server in server/gateway mode, and it's working pretty well, but I'm having some network performance issues that I think are related to the Proxmox virtualization it's running on (thread on that here: https://forum.proxmox.com/threads/poor-network-performance-on-guest.25502/).  It's been suggested that I add another LAN interface to my SME server for testing purposes.  All that would be required is for the interface to be active with an IP address.  The SME server wouldn't need to route traffic from it to the WAN (or vice versa), and no services would need to be listening on that IP.

No doubt I could look up how to do this in CentOS, especially since it will be a temporary change, but "the SME way" always discourages directly tinkering with the OS configuration.  Is there a more appropriate way to do this, or is this a case where just manually doing the configuration at the OS level would be better?
« Last Edit: January 07, 2016, 09:07:56 PM by DanB35 »
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Offline Daniel B.

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Re: Add a third NIC the "SME way"
« Reply #1 on: January 07, 2016, 04:05:25 PM »
If it's just a temporary change to test performance, you can hotplug your new NIC, and configure it using ifconfig. Only if you want permanent changes you'll need som emore work
C'est la fin du monde !!! :lol:

Offline DanB35

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Re: Add a third NIC the "SME way"
« Reply #2 on: January 07, 2016, 04:16:08 PM »
So something like
Code: [Select]
ifconfig eth2 192.168.2.3 netmask 255.255.255.0?  Seems simple enough.  I note that the manpage for ifconfig says it's obsolete, and to use ip instead.  Would that be an issue?
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Offline Daniel B.

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Re: Add a third NIC the "SME way"
« Reply #3 on: January 07, 2016, 04:17:18 PM »
you can use ip if you prefer, but ifconfig is still working
C'est la fin du monde !!! :lol:

Offline DanB35

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Re: Add a third NIC the "SME way"
« Reply #4 on: January 07, 2016, 04:18:42 PM »
Sounds good, thanks!
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Offline Stefano

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Re: Add a third NIC the "SME way"
« Reply #5 on: January 07, 2016, 04:19:43 PM »
search the forums (in french language too), you'll find the SME way ;-)

Offline DanB35

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Re: Add a third NIC the "SME way"
« Reply #6 on: January 07, 2016, 05:07:07 PM »
I found this thread: http://forums.contribs.org/index.php?topic=38614.0, but it's eight years old and two major releases out of date, and I don't see that it actually answers the question (it says, "don't do that" instead).  Following from that, it looks like there's been a bug open requesting this for about 10 years (bug 319, which has been superseded by bug 2669, which itself has been open nearly nine years), but the feature doesn't appear to have been implemented.

I did search the forums (specifically, I googled "add network interface site:contribs.org", which includes the forums), and got several hits, but nothing describing how to implement this, in the French section or elsewhere.  Was there a particular thread you had in mind?

For my purposes, Daniel B's suggestion should work--it's simple, it doesn't affect any configuration files, and it goes away when I reboot the server.  But if there's something else documented, it could be useful to someone else who might stumble on this thread.
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Offline Stefano

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Re: Add a third NIC the "SME way"
« Reply #7 on: January 07, 2016, 07:36:56 PM »

Offline DanB35

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Re: Add a third NIC the "SME way"
« Reply #8 on: January 07, 2016, 09:07:30 PM »
http://forums.contribs.org/index.php/topic,51604.0.html
Thanks for the pointer, I can see why my search didn't find it.  It looks like (if I can trust Google Translate) this solution does quite a bit more than I need, but it could certainly be helpful to others.
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