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New Member

Persistent link loss on 6509 switch

We have a 6509 switch that is basically used to connect Windows NT and 2000 servers on GBIC ports. Recently some of the servers started to loss link abruptly and gain again. The correct error description on the telnet session is as follows "Port x/y left bridge port x/y, Port x/y joined bridge port x/y". This was observed very infrequently at the beggining. Now we have a problem with almost every server that is connected to this module. In addition the link loss has become persistent and started to strongly disturb the normal function of the servers. Can anyone help me solve this problem?


New Member

Re: Persistent link loss on 6509 switch

Speed/duplex mismatches can cause links to flap.

What does your "sh counters mod/port" look like for these ports ?

New Member

Re: Persistent link loss on 6509 switch

There is no speed or duplex mismatch. Both sides are are configured for full duplex 1000. The show counter values are generally with in normal limit. One importnat info: When I connect the affected sever to another switch (4006) it will function with out any problem.


Re: Persistent link loss on 6509 switch

You may have to mess around with the flow control option , gigabit ports seem to be alot more sensitive to these , we have had to modify these on some of our gig ports . We couldn't just set the port speed and duplex , Sun nics are specially problematic .

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