NFS export from Synology to unRAID hangs entire unRAID server

[aneelley]

When I try to export a NFS mount from my Synology server over to my unRAID server, I am able to mount it with no issue.

 

However, when I try to just do a simple ls to confirm I can see the data in the mount, it just hangs and I am unable to ctrl-c out of it.  If I go to look at the shares on the unRAID server, that also hangs for ~10 minutes and then gives up.

 

I need some help trying to troubleshoot.  If someone can point me in the right direction on where to look for logs, that could help a bit.  I looked in /var/log/messages  but found nothing so that may be the wrong location.  Let me know.

[aneelley]

I should also add that when I try to stop the unRAID server so that I can remove the NFS mount, it won't stop.  It just hangs.

[aneelley]

I have been able to figure it out.  I disabled jumbo frames (MTU 9000) by setting it back to a MTU size of 1500.  I was then able to utilize the NFS mount as desired.

 

I do have a few questions though.  Why is it recommended to have a MTU size of 1500?  Is technology better now and MTU 9000 is no longer needed?  It was my thought that a MTU size of 9000 would allow bigger frames to be transmitted at once thereby giving more throughput and utilizing my network bond.

 

I am running a bond of 4 network ports (at least for now until I can get 10GbE configured) and didn't know if that came into play.

[dlandon]

Using Jumbo frames requires you set up all your network devices properely - router, switches, and all devices.  It's not that easy.

[aneelley]

Good point.  I DIDN'T have it set up on the switch which was probably why.  New switch will be here tomorrow so maybe I will try it out again.