Hello,
Few are here for your reference.
1. Verify all physical switch ports to be used for vMotion are configured for the correct VLAN and the MTU size is same for all ports used for vMotion in the physical network.
2. Verify that vMotion is not enabled on multiple vmkernal port groups.
3. Ensure that the subnet mask is consistent across all hosts and ensure that there are no IP address conflicts in the vMotion network.
4. Verify that there are no firewall rules restricting the local vMotion subnet.
5. Check the ESXi host's routing table to determine which vmkernel interface is used for each IP subnet. If multiple vmkernel ports exist in the same IP subnet, the one listed in the table is used when using the vmkping command:
# esxcfg-route -l
VMkernel Routes:
Network Netmask Gateway Interface
192.168.2.0 255.255.255.0 Local Subnet vmk1
192.168.3.0 255.255.255.0 Local Subnet vmk2
192.168.46.0 255.255.255.0 Local Subnet vmk0
default 0.0.0.0 192.168.46.2 vmk0
We can run the vmkping -I command to select the desired vmkernel interface to send ICMP traffic:
# vmkping -I vmkX x.x.x.x
Replace vmkX with the correct vmkernel interface, for example vmk1. Replacex.x.x.x with the IP address you wish to ping.
We can diagnose MTU- related issues by running the vmkping command:
# vmkping -I vmkX -d -s 8972 target.ip.address
Where vmkX is the vmk indicated for the vMotion interface on the host generating the ping traffic (source).
And target.ip.address is the IP address of the vMotion interface on the other host (destination).
-d = do not fragment the frame
-s = use this frame size.
MTU size of 8972 allows for some overhead but still allows the frame to go through. You can use something similar to 8000. Anything over 1500 is a valid test for jumbo frames. Remember that some physical switches need to be configured for MTU of 9216 to pass 9000 byte frames.
Hope this may helpful for resolving the issue