When you can't see your LUN…
There is several ways to troubleshoot an iSCSI connections. First of all, you should make sure that you can ping your iscsi network interface of your SAN. For this you can use command ping or you can use command vmkping.
For example you type: vmkping 192.168.5.10 where this IP adress is the IP adress of your iSCSI SAN. If you would like to enable Jumbo Frames, you could use vmkping -s 9000 192.168.5.10 to check if you can reach the destination point with the size of the packet 9000 (the right config for Jumbo Frames).
You must enable Jumbo frames on every hop in the iSCSI network for the configuration to work though …. 😎
Next you could try to edit the /etc/vmkiscsi.conf to add a carriage return after the final line of the file (this should be the discovery target).
You could also disable or enable the Software iSCSi initiator by issuing this command:
esxcfg-swiscsi -d
After, to enable again use this command:
esxcfg-swiscsi -e
To verify that the initiator is running you can do with:
esxcfg-swiscsi -q
To scan for new targets you can also do in CLI with:
esxcfg-swiscsi -s
Then in the GUI you can go to VI client and rescan the SAN storaby by going to:
Configuration > Storage adapters > Rescan
