if an llt link shows down, you can always inject some traffic through the wire and see if you can catch it on the other side.
We first, on one side of the cluster find out the mac address of our interface, then start a “dlpiping server”
process on it.
# /opt/VRTSllt/getmac /dev/ce:0
/dev/ce:0 08:00:10:A7:1E:DC
# /opt/VRTSllt/dlpiping -s /dev/ce:0
Now, on the other side of the link, on the other server, we query for the mac address in the wire.
# /opt/VRTSllt/dlpiping -c /dev/ce:0 08:00:10:A7:1E:DC
08:00:10:A7:1E:DC is alive
if it says that the mac is alive then we have a good link.