jappenroth
Enthusiast
Enthusiast

How to seperate NFS and VMotion traffic?

Jump to solution

Can I seperate network traffic to the NFS storage from VMotion?

If I create 2 vmkernel port groups "NFS" and "VMotion"on two different virtual switches how can I force the vmkernel to use the vmkernel port group "NFS" for the NFS datastore. There is a checkbox to select the proper port group for VMotion, but is there a way to select which port group to use for NFS?

Is there a way to tell which port group the vmkernel will select if there are multiple vmkernel port groups?

Thanks,

Jan

0 Kudos
1 Solution

Accepted Solutions
oreeh
Immortal
Immortal

this is the only possible way to do it - otherwise the VMkernel doesn't know which NIC to use

View solution in original post

0 Kudos
11 Replies
oreeh
Immortal
Immortal

If vmotion and NFS use different subnets the routing table will be used

0 Kudos
jappenroth
Enthusiast
Enthusiast

Hi oreeh,

what a lightning fast reply!

If vmotion and NFS use different subnets the routing

table will be used

So does that mean I have to put the IPs for VMotion and the NFS storage to different networks and then it will work?

I will try that. If it works I will come back and award points to you of course!

I still want to know if there is any way to achieve this.

Jan

0 Kudos
oreeh
Immortal
Immortal

this is the only possible way to do it - otherwise the VMkernel doesn't know which NIC to use

0 Kudos
enorthcraft
Enthusiast
Enthusiast

Can I seperate network traffic to the NFS storage

from VMotion?

Absolutely and this is the recommended method. You have two Vswitches which is great. You should implement discreet subnets for host traffic, NFS, and VMotion. I even suggest going one step further and creating a VLAN for each type of traffic. This can be done with physical adapters or 802.1Q tagging. Try to put VMotion traffic on a non-routable VLAN that is shared only with your hosts and VC.

If I create 2 vmkernel port groups "NFS" and

"VMotion"on two different virtual switches how can I

force the vmkernel to use the vmkernel port group

"NFS" for the NFS datastore. There is a checkbox to

select the proper port group for VMotion, but is

there a way to select which port group to use for

NFS?

Default routing tables will take care of sending traffic to the correct interface. With separate VLANs and subnets this will be easy.

Is there a way to tell which port group the vmkernel

will select if there are multiple vmkernel port

groups?

Again, default routing will apply. The interface on the same subnet will be used. If there isn't an interface with an address on the destination subnet, the default gateway will be used.

Good luck,

Eric

Eric Northcraft enorthcraft at gmail.com
KlinikenLB
Contributor
Contributor

Thanks to Jan for his question to this forum.

I will discuss this hints tomorrow with my (for the network responsible) collegue.

Regards, Dietmar

0 Kudos
Scripti
Contributor
Contributor

I tested the NFS mount in the vmkernel the last days.

I installed the SFU3.5 on my VC Server and configured a NFS Share.

I mounted the NFS share to the Service console and it works fine.

I configured a seperate vmkernel port group on the same vSwitch, where the port group for the service console and Vmotion is configured.

I tried to mount the NFS share into the vmkernel. I get the error message "permission denied". When I looked into the SFU log file, I saw, that the ESX host tries to mount the nfs share from the Vmotion IP and not with the vmkernel IP.

This is the behaviour as described here. But now I have some questions.

Why I have to enable the Vmotion check box when I create a Vmotion port group? In this case the Vmotion traffic should be transmitted over the Vmotion port group, or not?

In the vmkernel port group for NFS, I don't activate the Vmotion checkbox. So all other vmkernel traffic should be transmitted over this port group, or not?

0 Kudos
oreeh
Immortal
Immortal

Do you use the same subnet in the different port groups?

If yes this is your problem - if two interfaces have an IP in the same subnet (and aren't teamed) then the first matching interface will win.

0 Kudos
enorthcraft
Enthusiast
Enthusiast

One thing to consider is that each host as well as VC will need root write access to your NAS.

Can you post a brief network diagram? That will help us with your routing issues.

Eric Northcraft enorthcraft at gmail.com
0 Kudos
Scripti
Contributor
Contributor

Thanks for the fast response.

The service console, the Vmotion and the nfs port group are on the same subnet.

But did I unsderstand it right, I depends on the sequence of the port groups??

That means the first port group is for the service console. If the second port group is for Vmotion also the NFS traffic is transmitted over this one and the third port group for vmkernel-nfs is not needed.

But if I configure it in an other sequence, it will work? That means the first port group is also for the service console, and if the second port group is configured for the vmkernel-nfs and the third port group is configured for Vmotion, it works?? That means, the nfs traffic runs over the vmkernel-nfs and the vmotion traffic over the Vmotion port group??

0 Kudos
oreeh
Immortal
Immortal

The service console, the Vmotion and the nfs port group are on the same subnet.

this will never work

But did I unsderstand it right, I depends on the sequence of the port groups??

No - if you have several interfaces (regardless if physcial or virtual) belonging to the same subnet only ONE (the first) interfaceis used.

You either get the COS or VMkernel or vMotion working.

Message was edited by:

oreeh

as enorthcraft already requested: post a diagram of what you have / what you want

0 Kudos
enorthcraft
Enthusiast
Enthusiast

...we could really be more helpful with a network diagram...

For multiple physical interfaces on the same subnet, the OS will prefer (I believe) the adapter with the lowest index. You can find the index number using "ifconfig -a". You can also use "netstat -r" to show the routing tables and associated interfaces.

Eric Northcraft enorthcraft at gmail.com
0 Kudos