Hello!
Since upgrading our two test hosts to vSphere 6.5, they both lose connectivity to all 6 iSCSI targets. The iSCSI targets are all in the same subnet. Both hosts have two NICs. The NICs in host A are 1Gb, the NICs in the second host are 10Gb.
Initially, both hosts had separate vSwitches, and a dedicated NIC in each one. When connectivity is lost, neither NIC is pingable. We then moved the two NICs to a single vSwitch using the override so that the first vmk used the first NIC, and the second vmk used the second NIC. Lost connectivity again.
The hosts do no lose connectivity to the targets at the same time. That is, when host A loses its connectivity to the targets, Host B can still reach the targets. When host B loses its connectivity, Host A, can still connect to the targets. Also, the targets are still reachable by vSphere 5.5 hosts.
We just took one host down to one iSCSI NIC. It just lost connectivity. We are using an MTU of 9000. When things are working we are able to ping the host with ping -v -M do -s 8972 [ip address of vmk]
Thanks for any help!
