E1 networking include one 8630, one 8636 and ten 8066. L terminal can not connect with GK, the bridge has no warming; all the terminals of the branch company can not enter the conference only can see local image, the main terminal can enter normally. Restart E1 and all the terminals recover except L, some time later all the terminals become offline.
Examine the connection from terminal to GK and find the main terminal connect to switch directly the branch terminal connect to E1 bridge. So the fault is about bridge. Connect the switch and view the log we find: Loopback does exist on port 6 vlan1. The switch do not set off Vlan and physics port 6 has a ring. The port 6 corresponding terminal L. Check L’s line and the connection from L to DDF is OK, turn on and turn off the L bridge, we find the switch’s alarm disappeared after L’s bridge turn off, the switch’s alarm appeared when L’s bridge turn on. The ring is caused by L’s bridge. Check the connection from terminal to bridge and it is OK, can not find the point that made a ring. As the Yaaoshuma bridge has some fault before, so we replace the L’s bridge, then the fault is disappeared.
This problem is relate to network, and it is about the bridge. They become offline again is may caused by the ring.
Yaaoshuma bridge has made a lot of fault, we can not resolve it directly, so we can only replace the bridge. We should eliminate the problem from Yaaoshuma bridge firstly, than we do next.