May 13, 201511 yr Hi All, Now i have a strange issue here ... and wondering if anyone can help .. my network and switches support Jumbo packets.. so i have changed the unraid box to MTU 9000 configured it to stay after every reboot and now i cannot connect to the server via the network .... any ideas how to fix this?.. Cheers steve
May 13, 201511 yr Community Expert Put it back like it was? Maybe more complete information about exactly what you did?
May 13, 201511 yr Author Put it back like it was? Maybe more complete information about exactly what you did? Hi Trurl, Already pit it back... i edited the 'boot/config/network.cfg added MTU=9014' which all my systems are set to... all my machines are Intel® PRO/1000 Server Adapter NIC So they suport jumbo frames Any more info needed let us know Cheers Steve
May 13, 201511 yr i edited the 'boot/config/network.cfg added MTU=9014' which all my systems are set to... all my machines are Intel® PRO/1000 Server Adapter NIC So they suport jumbo frames You need to make sure the frame size on your hosts is smaller than the frame size on the switches and routers. So, if the switches and routers are set to a jumbo frame size of 9014, you need to make the host frame size small enough to allow the jumbo frame header to be attached. At least for testing, you can decrease the frame size a bit on the hosts to ensure the jumbo packet is making it through the network infrastructure. https://en.wikipedia.org/wiki/Jumbo_frame#Super_jumbo_frames http://www.mylesgray.com/hardware/test-jumbo-frames-working/ John
May 13, 201511 yr Author i edited the 'boot/config/network.cfg added MTU=9014' which all my systems are set to... all my machines are Intel® PRO/1000 Server Adapter NIC So they suport jumbo frames You need to make sure the frame size on your hosts is smaller than the frame size on the switches and routers. So, if the switches and routers are set to a jumbo frame size of 9014, you need to make the host frame size small enough to allow the jumbo frame header to be attached. At least for testing, you can decrease the frame size a bit on the hosts to ensure the jumbo packet is making it through the network infrastructure. https://en.wikipedia.org/wiki/Jumbo_frame#Super_jumbo_frames http://www.mylesgray.com/hardware/test-jumbo-frames-working/ John Hi John, Thank-you for the help... I know our equipment is allowing jumbo packets / Frames through as i have recently discovered that one of our machines on the network has access to the server without a hitch.. - Lets call it system 1 - ... i have checked the settings on both Systems 1 & 2, they are duplicate to each other but i cant access on system 2... What i have also discovered is if i have the servers MTU set 9014 and set system 2 jumbo packets to disabled i can connect to the server fine and achieve transfer rates of over 100MB/s......... Which has confused me slitly as when the server is at default values i get between 10 / 20 MB/s Any ideas ? Hardware for both system 1 & 2 Acer Veriton X4620G Intel® PRO/1000 Server Adapter NIC 16GIG DDR3 Ram Intel I5 WINDOWS 8.1 ' Both Fresh installs ' Cheers Steve
May 13, 201511 yr What i have also discovered is if i have the servers MTU set 9014 and set system 2 jumbo packets to disabled i can connect to the server fine and achieve transfer rates of over 100MB/s......... Which has confused me slitly as when the server is at default values i get between 10 / 20 MB/s Any ideas ? What I believe is happening (it's been a few years since this was my daily work focus) is that when one system is set for jumbo, and the other is not, the network switch in between is fragmenting the packets for you, as it knows that one system can't handle the jumbo frames. What type of network equipment is between the two servers? Can you confirm the jumbo frame size on that switch/switches? If you assume the switch is set to 9000+buffer, then I'd set both servers to a jumbo frame size of 9000 and test. If that doesn't work, set each server to a jumbo frame size of 8968 and test. Either way, you should have a lot fewer packet disassembly and reassembly activities that you would with a standard Ethernet frame size of 1500 bytes + buffer overhead. John
May 13, 201511 yr Author Hi John, I sincerely apologize here ..... after getting frustrated i decided to reboot the network .... and systems that are on it ... leaving all the settings how i changed them it all appears to be working i apologize for the waste of time .... and thankful for the help Cheers Steve
May 13, 201511 yr Hi John, I sincerely apologize here ..... after getting frustrated i decided to reboot the network .... and systems that are on it ... leaving all the settings how i changed them it all appears to be working I'm glad to hear its working! Now be sure to test to see you are getting the performance you would like to see. John
Archived
This topic is now archived and is closed to further replies.