Comments on: VMware vSphere vDS, VMkernel Ports, and Jumbo Frames http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/ The weblog of an IT pro specializing in virtualization, storage, and servers Wed, 08 Feb 2012 17:13:47 +0000 hourly 1 http://wordpress.org/?v= By: Oliver http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/comment-page-1/#comment-50286 Oliver Thu, 17 Feb 2011 12:41:46 +0000 http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/#comment-50286 Hi, found out that when you create the switch locally and later migrate it to dVS you can also migrate the VMKernel network interface without commandline. Regards Oliver Hi,

found out that when you create the switch locally and later migrate it to dVS you can also migrate the VMKernel network interface without commandline.

Regards
Oliver

]]> By: slowe http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/comment-page-1/#comment-48950 slowe Tue, 17 Aug 2010 11:35:20 +0000 http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/#comment-48950 Bryan, With regard to jumbo frames, you'll need end-to-end support for jumbo frames: from the ESX/ESXi host through all switches and on to the storage array itself. As for other types of traffic, enabling jumbo frames on a VMkernel port affects only the traffic going through that VMkernel port. So, if you have a VMkernel port for IP-based storage traffic for which jumbo frames is enabled and you have a different VMkernel port you are using for vMotion that has not been enabled for jumbo frames, then only the IP-based storage traffic is affected. Enabling jumbo frames at the physical switch level (or even at the virtual switch level, for that matter) doesn't do anything until the endpoints are configured to use/support jumbo frames. I hope this helps. Good luck in your implementation! Bryan,

With regard to jumbo frames, you’ll need end-to-end support for jumbo frames: from the ESX/ESXi host through all switches and on to the storage array itself.

As for other types of traffic, enabling jumbo frames on a VMkernel port affects only the traffic going through that VMkernel port. So, if you have a VMkernel port for IP-based storage traffic for which jumbo frames is enabled and you have a different VMkernel port you are using for vMotion that has not been enabled for jumbo frames, then only the IP-based storage traffic is affected. Enabling jumbo frames at the physical switch level (or even at the virtual switch level, for that matter) doesn’t do anything until the endpoints are configured to use/support jumbo frames.

I hope this helps. Good luck in your implementation!

]]> By: Bryan http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/comment-page-1/#comment-48949 Bryan Tue, 17 Aug 2010 01:49:47 +0000 http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/#comment-48949 Hi Scott, First off, great post. We are deploying blade infrastructure with 2 x 10 gigabit NIC's attached to a single dvSwitch which will provide for all network requirements (i.e. Management, VMotion, Virtual Machine LAN traffic & NFS storage traffic) We plan to configure the physical infrastructure, dvSwitch and vmkernel port groups (NFS and VMotion) for Jumbo Frames. My question is similar to Vinod's above around what will happen to the virtual machine and management traffic? Will they be fragmented by the LAN switches up stream? thanks Bryan Hi Scott,

First off, great post.

We are deploying blade infrastructure with 2 x 10 gigabit NIC’s attached to a single dvSwitch which will provide for all network requirements (i.e. Management, VMotion, Virtual Machine LAN traffic & NFS storage traffic)

We plan to configure the physical infrastructure, dvSwitch and vmkernel port groups (NFS and VMotion) for Jumbo Frames.

My question is similar to Vinod’s above around what will happen to the virtual machine and management traffic? Will they be fragmented by the LAN switches up stream?

thanks
Bryan

]]> By: Vinod http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/comment-page-1/#comment-48352 Vinod Tue, 11 May 2010 17:42:32 +0000 http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/#comment-48352 Scott, I have two NICs. One is sharing Service console and VMKernel Port. The other is used for Virtual Machine Port. In this scenario can we still use Jumbo Frames. If yes, how would service console behave? Scott,
I have two NICs. One is sharing Service console and VMKernel Port. The other is used for Virtual Machine Port. In this scenario can we still use Jumbo Frames. If yes, how would service console behave?

]]> By: padra1g http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/comment-page-1/#comment-47864 padra1g Wed, 14 Apr 2010 13:53:16 +0000 http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/#comment-47864 if i change my vm client eth0 mtu to 9000 i cannot ftp/scp to work. However ssh/ping are ok. To get ftp/scp to work i need to set mtu to 1500 any suggestions? thanks, p. if i change my vm client eth0 mtu to 9000 i cannot ftp/scp to work.
However ssh/ping are ok.
To get ftp/scp to work i need to set mtu to 1500 any suggestions?

thanks,
p.

]]> By: Tom Miller http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/comment-page-1/#comment-47746 Tom Miller Tue, 23 Mar 2010 02:35:32 +0000 http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/#comment-47746 Scott, The command above will not work for ESXi infrastructures: 3 # Recreate the VMkernel port and attach it to the very same dvPort ID: esxcfg-vmknic -a -i -n -m 9000 -s -v Please see forum article for workaround, it's clugy, but it works. Thanks to MarkEwert for the advice in the article and thanks to you for all your great post. Here is the forum article: http://communities.vmware.com/thread/254623 Scott,
The command above will not work for ESXi infrastructures:
3 # Recreate the VMkernel port and attach it to the very same dvPort ID:
esxcfg-vmknic -a -i -n -m 9000 -s -v

Please see forum article for workaround, it’s clugy, but it works. Thanks to MarkEwert for the advice in the article and thanks to you for all your great post. Here is the forum article:
http://communities.vmware.com/thread/254623

]]> By: slowe http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/comment-page-1/#comment-47727 slowe Sun, 21 Mar 2010 19:40:34 +0000 http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/#comment-47727 Aenagy, All port groups might have to have the same MTU, but you should be able to configure the MTU on a per-VMkernel port basis (and possibly a per-Service Console connection, too). I'll look into that... Aenagy,

All port groups might have to have the same MTU, but you should be able to configure the MTU on a per-VMkernel port basis (and possibly a per-Service Console connection, too).

I’ll look into that…

]]> By: aenagy http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/comment-page-1/#comment-47726 aenagy Sun, 21 Mar 2010 19:36:51 +0000 http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/#comment-47726 I was in a hurry so I opened a case with VMware technical support. The short answer is no, you can't configure port groups in the same vSwitch with different MTU values. I was in a hurry so I opened a case with VMware technical support. The short answer is no, you can’t configure port groups in the same vSwitch with different MTU values.

]]> By: aenagy http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/comment-page-1/#comment-47715 aenagy Thu, 18 Mar 2010 23:01:20 +0000 http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/#comment-47715 ... forgot to mention that this question is for ESXi 4.0.0 Update 1. … forgot to mention that this question is for ESXi 4.0.0 Update 1.

]]> By: aenagy http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/comment-page-1/#comment-47714 aenagy Thu, 18 Mar 2010 22:59:17 +0000 http://blog.scottlowe.org/2009/05/21/vmware-vsphere-vds-vmkernel-ports-and-jumbo-frames/#comment-47714 Noob question: Is it possible to configure the vSwitch for jumbo frames, but configure individual port groups to not use jumbo frames? I ask because our VMware PSO engagement is recommending that we combine Management and VMotion in the same vSwitch/NIC team but on separate port groups. Within each port group a different vmnic in the team/vSwitch would be configured as active and the other vmnic as standby. Like this: vSwitch0 PortGroup1: Management vmnic0 : active vmnic1 : standby VLAN : x PortGroup2: VMotion vmnic0 : standby vmnic1 : active VLAN : y We don't want jumbo frames for the 'Management' port group as these packets need to be routable and the rest of our network will not be configured to support jumbo frames. We do want jumbo frames for the 'VMotion' port group as these packets will never leave the pSwitches and will be configured to support jumbo frames. Noob question:

Is it possible to configure the vSwitch for jumbo frames, but configure individual port groups to not use jumbo frames?

I ask because our VMware PSO engagement is recommending that we combine Management and VMotion in the same vSwitch/NIC team but on separate port groups. Within each port group a different vmnic in the team/vSwitch would be configured as active and the other vmnic as standby. Like this:

vSwitch0
PortGroup1: Management
vmnic0 : active
vmnic1 : standby
VLAN : x
PortGroup2: VMotion
vmnic0 : standby
vmnic1 : active
VLAN : y

We don’t want jumbo frames for the ‘Management’ port group as these packets need to be routable and the rest of our network will not be configured to support jumbo frames. We do want jumbo frames for the ‘VMotion’ port group as these packets will never leave the pSwitches and will be configured to support jumbo frames.

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