creating vmkernel port breaks connectivity to management network

[willi321]

cisco ucs 220 v4 server

esxi 5.5 custom image for cisco

2 physical 2 vmnics

currently have 1 vswitch. managment network(vmnic0) is configured on this vswitch.    trying to setup vmkernel port for iscsi traffic using the other nic/vmnic1. i am able to click through and configure from the 'add network wizard' and when i click finish, vsphere spins and spins. after a minute it is no longer able to communicate over management port. i have to log into the console of esxi and restore network settings and then re ip the management network to get reconnected.

what am i doing wrong? any help would be appreciated. Thank you

[chr1s86]

Check your Teaming/Failover options and the underlay VLAN config of your Network.

Maybe the issue is also in UCS VLAN mapping. Pics of your vswitch and vmk config would help ...

[willi321]

when you say to check the failover option, are you referring to the physical hardware or within esxi?  i will obtain a pic of the network config within esxi when i return to client site. greatly appreciate you chiming in on this. please let me know if anything else comes to mind. Thank you

[willi321]

The data vlan (1) and the iscsi vlan (2) are both configured on the 2 physical  switch ports in which physical nics are plugged in. I dont have the vmkernel port from esxi tagged either. Could either of these configurations be causing the issue?  Seems to align with your suggestions.

[chr1s86 · Accepted solution]

If you have a two different VLANs you should tag them, or at least one of them.

Make sure you have exact the same underlaying NIC konfig. In your case i would suggest:

Leave VLAN1 untagged as Management Network, konfigure your VLAN2 as tagged VLAN.

When you now have a single vswitch0 with that two uplinks (lets say vmnic0 and vmnic1). Each uplink has VLAN1 native and VLAN2 tagged.

You configure your Management Network with vmnic0 active and vmnic1 as standby.

For ISCSI you do it vice versa vmnic1 active and vmnic0 as standby.

With this configuration, you could be sure, that your Management Network and ISCSI use in normal operation different NICs. Only if a NIC Fails, the other one can handle the traffic too.

Before going to production, test your failover!

Also Check:

https://docs.vmware.com/en/VMware-vSphere/6.5/vsphere-esxi-vcenter-server-65-networking-guide.pdf