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Basic question?

If you have two switches connected to each other, then you have server 1 connected to SW1 and Server 2 is ocnnected to SW2. Server 1 and 2 are on the same VLAN, however no traffic is passing between the 2 servers. Is that normal that the MAC address od Server2 will disappear from the MAC-Address-table of Switch1. If you try to ping, the MAC will appear however it will disappear agin after the aging time expire. If it's not normal, will that create anp problem?

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Re: Basic question?


Yes it is perfectly normal. Unless the mac address entry has been statically configured the switch will eventually time it out.

It is nothing to worry about.



Re: Basic question?

It seems normal to me. The only consequence is that when traffic for that server arrives at the switch and the MAC address is not in the table then it'll be broadcast to all ports in the VLAN (broadcast domain).


Re: Basic question?

It is perfectly normal and how a switch works .There is mac address ageing timer in the switch , usually 5 minutes unless you hardcode it to another value . It gets flushed out if it sees no traffic from that device within that period .If you didn't have this the mac table would continue to grow to the point the switch could not handle it , each switch has a set amount of mac addresses it can handle . I'm not sure what happens if you get to the max mac table , it may start flushing the oldest entries first then you get into a scenario where you get a lot of broadcasting going on .

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