Create Date: Aug 1 2013 10:05AM
If You want to connect cisco and extreme networks with link status check so unfortunately UDLD and ELSM is not compatible. You should disable UDLD on cisco and ELSM on extreme on uplinks, otherwise for ex. if you have four switches in ring (E2<-> C1<->C2<->E1<->E2<->C1) and C1 loses connection to E2, UDLD will think that link is broken and will disable port on C2<->E1, so You loses connection between cisco and rest of extreme switches. (from karpiu)