Unraid as Network Switch / Bridging - Config breaks networking entirely

[Jojomatik]

Hi,

I'm running an unraid machine in my basement and I'm currently trying to setup a direct 10G connection between my PC and the unraid machine additional to the normal 1G link through multiple switches.

The basic idea is to disable bonding and enable bridging on the first network card, but every time I do that the network connection is dropped completely and I'm unable to change the settings back of course as the Web GUI is unaccessible. Therefore I have to grab the thumbdrive and delete the network config file manually every time, which makes debugging very tedious.

I've already posted this in the unraid forums around a week ago and haven't received any answers. Not sure if my question lacks information or is unclear, as I'm relatively new to unraid, servers, more "complex" networking than just plugging in a cable etc. or if the community in the unraid forums is just as clueless as I am. Any help or debugging tips would be appreciated. I would like to minimize the downtime during testing as I host multiple services for friends and family and don't want to disturb their workflow.

My Post on the Unraid forums

 

Basic summary of the linked posts in my unraid post:
 

Quote

For eth0:

- Enable bonding = No

- Enable bridging = Yes

- Bridge members = eth0, eth1

 

For eth1 (will get automatically added to the eth0 bridge)

- Enable bonding = No

- Enable bridging = No

But if I disable eth0 bonding and enable bridging (add eth1) and leave everything else unchanged, unraid looses network connectivity. Therefore I have to take the thumbdrive and delete network.cfg.

 

What am I doing wrong?

Additional information:

• I'm running Unraid 6.8.3.
• I'm currently also connected to the router from my PC. Is this a problem? (I can't use the 10G direct link currently as its not configured yet)
• The 10G connection shows up in windows but is unconfigured (as expected).

This is the config that causes the network connection to drop: (Therefore "Please wait" and the loading animation persist)

MAC-Adresses and PCI device details removed (not even sure if somebody could use this information for something evil, but I'd rather remove to much than to little :D)

Thank you for your help and time!

Edit: Just realised that the networking subforum might be more fitting. @Moderators feel free to move, if you agree (I don't think I'm able to on my own).

Edited December 4, 2020 by Jojomatik
Maybe wrong forum?

[Electronics Wizardy]

6 hours ago, Jojomatik said:

The basic idea is to disable bonding and enable bridging on the first network card, but every time I do that the network connection is dropped completely and I'm unable to change the settings back of course as the Web GUI is unaccessible. Therefore I have to grab the thumbdrive and delete the network config file manually every time, which makes debugging very tedious.

can't you edit the config from the cmd line on the server? That would make trouble shooting much easier.

 

I belive you just want to make both of the nics part of br0, and then you don't need to configure anything on the nic settings themselves. I don't use the gui here too much, look at the network config file aswell.

[Jojomatik]

1 hour ago, Electronics Wizardy said:

can't you edit the config from the cmd line on the server? That would make trouble shooting much easier.

Thanks for the response. My quick google search tells me the network config should be located at 

/boot/config/network.cfg

but unfortunately there is no file currently, so I can't verify that. I think it is just not generated as long as i use the default settings.

I don't think this solves my troubleshooting problem as the network connection is dropped completely so using the SSH console won't help. Or do you say I should use the console on the machine directly by attaching a monitor and keyboard? That would be possible but would take some time and work.
 

1 hour ago, Electronics Wizardy said:

I belive you just want to make both of the nics part of br0, and then you don't need to configure anything on the nic settings themselves. I don't use the gui here too much, look at the network config file aswell.

I'm not really familiar with this file, is it the same as with other linux based systems or an unraid specific format?

Would you be so kind and provide a sample config that should work?

I just remembered I made a copy of the network.cfg config, before I deleted it to go back to the default settings:
 

# Generated settings:
IFNAME[0]="br0"
BRNAME[0]="br0"
BRSTP[0]="yes"
BRFD[0]="0"
BRNICS[0]="eth0 eth1"
PROTOCOL[0]="ipv4"
USE_DHCP[0]="yes"
DHCP_KEEPRESOLV="no"
USE_DHCP6[0]="yes"
DHCP6_KEEPRESOLV="no"
SYSNICS="1"

 
I think is in line with what you suggested. Would it be possible that the system is confused, on which interface it should use DHCP?

Should I turn it off and add a static IP (I know this recommended anyway but I kindof forgot about it and didn't run into any problems yet)?

What does DHCP_KEEPRESOLV do? Seems to have something to do with the resolv.conf, but I wouldn't mind if it would be overwritten by DHCP or should I?

[Jojomatik]

Seems like i finally fixed it.

I switched to a static IP (which required a restart of the unraid machine).

And after that I used my config in the screenshot above (No restart required here).
 

@Electronics Wizardy: Even though you didn't directly point my to the right solution (i mean what you said is stilltrue, but I already had it configured that way) by pointing me to the config file, you at least lead me to rethink that DHCP on 2 NICs might cause confusion on the systems side. Thank you