vSphere 5 iSCSI Disconnects Setting Virtual Distributed Switch to Jumbo Frames Using Hardware iSCSI Initiator
OK readers, I've got a task I need help with. My vSphere 5 license keys don't allow me to report bugs to VMware and since I'm running vSphere on my Shuttle Boxes, they would automatically call me out on not being on the HCL. I'm asking for someone with a few minutes and a setup they can break to please test something out.
I'm currently rebuilding my lab from vSphere 5 beta build 384847 to vSphere 5 GA build 469512. vCenter is running GA build 455964. I try to mimic a 10GbE environment by using everything on 2 1GbE NICs sitting on a Virtual Distributed Switch (vDS). The issue rises when setting the MTU on the vDS to anything greater than 1500 MTU. I need to set the vDS to atleast 1524 MTU for a nested vCloud Director environment. When setting the vDS to a number greater than 1500, my iSCSI datastores all disconnect. This setup worked perfectly on vSphere 4.1 and even on vSphere 5 beta. I have a feeling that the issue is with vCenter 455964 and the vDS, but not the actual host itself because the ESXi host running build 384847 was running fine until I had to rebuild my vCenter server. The switch connecting all this is a HP ProCurve that supports Jumbo Frames and is turned on. This is all done using the hardware iSCSI initiator that is baked into my Broadcom BCM5709 NICs. So only test this if you have NICs that are capable of doing iSCSI and not utilizing the Software iSCSI Inititor provided by VMware.