Hello all,

I had some time this week to tinker around with my Unraid machine, and noticed the new docker setting "Host access to custom networks:" on the Settings -> Docker page.

I enabled it, even though I wasn't sure I needed it, but I wanted to play around.

Immediately I noticed that my router went bonkers, complaining of a ton of IP conflicts. I use Arpwatch on PFSense, and it was complaining about a ton of IP's being assigned to multiple MAC addresses. Turns out this is expected behaviour, because the way that "Host access to custom networks" works is by creating a bunch (in my case anyway, with a few VLANs on my machine) of extra "shim" network interfaces. For reference: 

 

  

Today however I noticed a second ... thing. My Windows 10 VM (on Unraid) started having connectivity problems to my local Network shares (also on the same Unraid machine). All worked fine for weeks before this setting was turned on.

 

The symptoms for me, was that if I used my VM (which lives on a VLAN bridge interface) to say, create a torrent file from a file that it was accessing from a share, it was running fine for a few seconds, and then freezing, and then marking itself completed. The torrent files were being filled with "null" values, and were invalid. I also had it try to recheck a known good torrent file, and this one failed as well - it rechecked for a few seconds, and then died. The torrent client reported an I/O error and killed the recheck process.

 

Disabling the "Host Access Custom Networks" setting rectified the problem. The checks completed successfully immediately.

 

I'm not sure exactly why I'm posting except maybe in case anyone else has issues after enabling this setting like I did.

 

Edit to add, I have diagnostics (from after the setting is turned off) but I'm not really comfortable sharing even the anonymised ones publicly. I can send 'em directly if someone is interested though.

Edited May 11, 20206 yr by Chunks
improved link

I have also been having issues with my network since enabling Host Access Custom Networks. Today I had both my switch and unraid completely lock up which has never happened before. (Not ruling out it being a different issue) Another issue I have been having is Host Access Custom Networks being enabled but the SHIMS never being created.