Cannot Change IP on Interface through GUI

[artlessknave]

enterprise level software

technically SCALE isn't enterprise level yet. they currently recomend against using it for production.

 

[Patrick M. Hausen]

Folks, what are we discussing here? The OP correctly identified that one needs to create an alias for a static IP address and that nothing happens after clicking "save". So far so good.

The missing piece is that after that step you need to

- click "test settings" in the upper left region of the UI and then
- within 60 seconds reconnect and login to the UI using the new static IP address and then
- click on "save settings" in the dialog box presented after login

Worked perfectly well every time I tried it and is part of the anti lockout two step process of applying and saving changes to the network settings. This part of the UI in SCALE and in CORE is really pretty damn good! One can even change the 60 seconds timeout to e.g. 300 in case one wants an LACP setup and needs to reconfigure the switch after the NAS. That also worked way more than once, here.

 

[paddy01]

From an earlier reply it looks like you’re trying to configure multiple interfaces in the same subnet.

That’s generally a no in TrueNas.

 

[ApexProxy]

Folks, what are we discussing here? The OP correctly identified that one needs to create an alias for a static IP address and that nothing happens after clicking "save". So far so good.

The missing piece is that after that step you need to

- click "test settings" in the upper left region of the UI and then
- within 60 seconds reconnect and login to the UI using the new static IP address and then
- click on "save settings" in the dialog box presented after login

Worked perfectly well every time I tried it and is part of the anti lockout two step process of applying and saving changes to the network settings. This part of the UI in SCALE and in CORE is really pretty damn good! One can even change the 60 seconds timeout to e.g. 300 in case one wants an LACP setup and needs to reconfigure the switch after the NAS. That also worked way more than once, here.

I know how the system normally sets an alias. My issue is nothing is being set when attempting to do so.

Normally when you click "Save" it closes the popup and then you go to "test settings" and then "save settings". My issue is, when I click 'save" the popup persists and "save becomes grayed out. Proceeding to test results in the alias for that interface being left blank.

 

[ApexProxy]

From an earlier reply it looks like you’re trying to configure multiple interfaces in the same subnet.

That’s generally a no in TrueNas.

Yeah, that does appear to be my issue. However, by using DHCP on one interface and an alias on another I am able to get it to do just that. The issue only arises when I try to turn off DHCP and set an alias on both interfaces.

 

[Patrick M. Hausen]

Anyway even with DHCP this is an invalid configuration according to all IP standards. One subnet, one interface. You can put as many addresses as you like on one as aliases.

What are you trying to achieve with that configuration?

 

[ApexProxy]

Also, this is what happens in the console:

eno1 is set via alias to 10.0.1.4/16 and br50 is DHCP off and no alias.

If I attempt to set br50 to an alias of 10.0.1.2/16 this is what I get.

If I then just turn on DHCP on br50 it then picks up 10.0.1.2/16 since I forced a static via my DHCP server.

So after testing I discovered this workaround and everything seems to be working fine even though both are on the same subnet.

Does anyone have insight into why double interfaces to the same subnet is bad? I'm quite new to networking as a whole, this is a home lab intended to help me learn. So please, if this is terrible and I shouldn't ever do this I would like to know the reason(s) why and not just that I shouldn't.

 

[ApexProxy]

Anyway even with DHCP this is an invalid configuration according to all IP standards. One subnet, one interface. You can put as many addresses as you like on one as aliases.

What are you trying to achieve with that configuration?

My goal with this is some simple load balancing and allowing for redundant paths to manage the server. Mainly, to learn about what I can and can't do with a network really.

 

[paddy01]

My goal with this is some simple load balancing and allowing for redundant paths to manage the server. Mainly, to learn about what I can and can't do with a network really.

In which case, assuming you have a managed switch you can configure, LACP is what you’re looking for.

 

[Patrick M. Hausen]

Does anyone have insight into why double interfaces to the same subnet is bad?

It's not "bad". It doesn't work. It violates IP addressing and routing standards. Simple as that. A host is supposed to pick one connected interface for any locally connected network.

You can achieve load balancing and redundancy on layer 2 - that's called LACP and needs support on the other end of the connection, in most cases your switch.

Or you can do it on layer 3 using two different subnets, and something called equal cost multipath routing.

Please read https://www.truenas.com/community/resources/multiple-network-interfaces-on-a-single-subnet.45/

HTH,
Patrick

 

[ApexProxy]

Interesting. I have heard of LACP but haven't looked into it yet so I definitely will. Thanks.

I started poking around trying to learn the why behind the "don't do it" and I see some interesting results. It seems that the biggest issue is sometimes you cannot be sure which interface is being used for what which makes sense. I'll keep exploring to see what else I can find.

 

[ChrisRJ]

For a solid background understanding of networking I can recommend "Computer Networks" by Andrew Tanenbaum. You should also be able to find a used older edition for cheap, which will likely be more than enough.

 

[ApexProxy]

For a solid background understanding of networking I can recommend "Computer Networks" by Andrew Tanenbaum. You should also be able to find a used older edition for cheap, which will likely be more than enough.

Thank you very much for the recommendation.

 

[ApexProxy]

So, I encountered an issue when attempting to change to the recommended configuration you guys are pushing me towards. I started off with the interface eno1 given an alias of 10.0.1.4/16 and a bridge (br50) containing the interface eno49d1 being directed to DHCP which was giving it a static of 10.0.1.2/16.

I communicate with the server via 10.0.1.2 but for some unknown reason br50 has a weird tendency to (while still on DHCP) to suddenly hop to a 192.168.0.0/16 address even though I have no such DHCP server and it breaks communication if it is the only interface. This just happened when I attempted to disable eno1 and go with a single interface as recommended and I am super confused as to what this phantom address is coming from. I am about to dig around in my switch (it is an L3) to make sure it's DHCP server wasn't turned on somehow?

UPDATE: Ended up using cli --menu to clear the alias off eno1 and force one onto br50 and just stop using DHCP on it entirely. This decision came after plugging in my console cable to poke at the switch and my desktop suddenly getting a BSOD and the console cable getting crazy hot. Cheap piece of junk. New one on the way. Sign...