Two NIC's for the average home user - config help

[SilverJS]

Gents,

So I got this shiny new SuperMicro mobo - great for IPMI, but these two NIC's are probably way overkill for me. I keep seeing all these messages in my console about how the MAC address keeps changing - I wonder if it's because I've never truly, properly configured the interfaces?

When I first set up the board, I just did as I usually do on a single-LAN board : I configured the interface (one interface, that is) for IPv4, and that's that. Never touched the other one. Both NIC's are connected to a dumb switch, btw.

Regardless of whether or not my MAC messages (which don't seem to harm anything anyway) are only nuisance or serious, I'd like to do this right. Should I configure a LAGG for failover? (I know my switch doesn't support LACP.) Or should I simply unplug the second cable and be done with it?

Cheers!

 

[pirateghost]

You shouldn't have both plugged in if you aren't using the second one. Don't mess with LACP/LAGG since you don't have the proper hardware

 

[DrKK]

Why does this post sound identical to at least two other posts in the past month? Even the words used.

Am I imagining it?

 

[SilverJS]

Does it...? Apologies, I really did search (always do).

Sounds good, I'll just unplug then.

 

[Ericloewe]

Why does this post sound identical to at least two other posts in the past month? Even the words used.

Am I imagining it?

Now that you mention it, I have that feeling too. At first, I just thought I'd already read it once or twice before, but the threads evolved differently.

 

[jgreco]

I'd put a bug report in that an error should be logged if two DHCP interfaces are brought up on the same network, but I have little faith that there's any interest in putting in such error-detecting functionality.

 

[SweetAndLow]

I'd put a bug report in that an error should be logged if two DHCP interfaces are brought up on the same network, but I have little faith that there's any interest in putting in such error-detecting functionality.

Ummm, no? This doesn't make any sense, it's perfectly fine to have two interfaces on the same network. What an I missing here? I have one interface dedicated to jails and the other to smb traffic.

 

[jgreco]

It's an invalid configuration. It actually works, but it probably doesn't work the way you think it is working. Please read the sticky in the networking forum about it. It is "broken" in one of those ways that's harmless unless you're actually expecting that the second interface behaves in a very particular manner, which is usually what Windows washers expect will happen. ;-)

 

[SweetAndLow]

It's an invalid configuration. It actually works, but it probably doesn't work the way you think it is working. Please read the sticky in the networking forum about it. It is "broken" in one of those ways that's harmless unless you're actually expecting that the second interface behaves in a very particular manner, which is usually what Windows washers expect will happen. ;-)

That post was about nic bonding and how it doesn't work the way people think it works. I understand that but I interpreted your comment to include configurations that don't include nic bonding. Just pain old interfaces on a network configured with separate IPs. I think that a configuration with multiple interfaces on the same network makes sense.

 

[pirateghost]

But it doesn't make any sense to have 2 NICs on the same network. There is no benefit

 

[jgreco]

Of course you do, and, yes it kind of works, however it probably does not work the way that you expect. In particular, Traffic is not guaranteed to originate from the interface containing the IP number that the client is talking to. Further, this configuration can lead to all sorts of interesting problems with ARP.

 

[jgreco]

But it doesn't make any sense to have 2 NICs on the same network. There is no benefit

And some potential for harm. In any case, gentlemen, I am currently doing house renovation work and I am 20 miles from a real keyboard, so I am not going to continue this discussion at this time. Voice-dictating technical messages sucks. The simple fact of the matter is that, while it may work for some definition of the word work, it is an invalid configuration and may cause problems.

 

[SweetAndLow]

But it doesn't make any sense to have 2 NICs on the same network. There is no benefit

What if you have multiple workflows on your network and file server and want to provide adequate service for each workflow. You can use one interface for file sharing and the other for video editing. This makes sense in a multi client workflow.

Of course you do, and, yes it kind of works, however it probably does not work the way that you expect. In particular, Traffic is not guaranteed to originate from the interface containing the IP number that the client is talking to. Further, this configuration can lead to all sorts of interesting problems with ARP.

How can it cause problems with arp? Each interface has it's own mac address which would create a unique entry in the arp table and look like 2 different end points to the network. I also don't think traffic will leave a different interface than it was received on. The fd created in the OS that the process reads and writes to can't just switch to a different interface in the kernel.

 

[jgreco]

This is the sort of failure to understand that I am more or less tired of explaining to people. Please go read the multiple interfaces sticky in the networking forum.

it does not operate anything like the way you describe.

 

[cyberjock]

This is the sort of failure to understand that I am more or less tired of explaining to people. Please go read the multiple interfaces sticky in the networking forum.

it does not operate anything like the way you describe.

This. It doesn't work how you think it works. There is NO guarantee that if you go to 192.168.0.10 instead of 192.168.0.11 that the traffic is actually being routed out that interface.

Yes, it has been discussed to death. Please read the sticky. It was written because we were tired of discussing it.

 

[Black Ninja]

That is true. You both already said several times that LACP is for 10+ users and that Multiple interlace on same network is no good. But I wonder how come nobody explains what is the proper way to setup Freenas without LACP to balance several(less than 10 clients) clients on a small network. I am keep jumping from one forum to another trying to find such information , but keep stumbling on the same things..

There is so much fuss and confusion about LACP what it is and what is not , but nowhere I can find a solution how to properly balance few client to take advantage of multiport nics , without getting in to LACP ?

P.S. If I am wrong and there is such a info , I would greatly appreciate if somebody provide a link to it. I read a lot of helpful info , but nothing actually like a solution ?

 

[jgreco]

That's because LACP is the standard technology to do this. The non-LACP alternatives are to use multiple (i.e. separate) networks or to upgrade to 10GbE.

 

[Black Ninja]

How about if quad port nic on freenas is made like this:

every single link is on different sub net and ip so the server can aggregate 4 links for 4 clients who will access the freenas by the ip on that particular subnet ?

All 4 clients can send or receive from Freenas in the same time , right ?

 

[jgreco]

That is a unique definition of the word "aggregate.". It's four separate networks, no one I know of would call it aggregation.

It would work just fine, of course.

 

[Black Ninja]

I would call this technology " Link Aggregation without link Aggravation":D