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STP port state question
borumas
Member Posts: 244 ■■■□□□□□□□
in CCNA & CCENT
I remember a question on what port states does a switch port learn mac addresses? Am I right in thinking it learns them only in learning and forwarding modes? From the info I've read that seems to be the case but I thought I had once read that while blocking a port that it still receives bpdu's, does it also possibly learn macs in this state also?
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EdTheLad
Member Posts: 2,111 ■■■■□□□□□□
Yes you are correct, only learns in learning and forwarding mode.Networking, sometimes i love it, mostly i hate it.Its all about the $$$$ -
OptionsNetstudent
Member Posts: 1,693 ■■■□□□□□□□
yes and blocking states do listen for BPDU's but they don't build cam tables in blocking. If you review a BPDU frame format and the source and destination MAC fields, you will see that these are MAC's of the swithes themselves. The base macs. I don't think these MACs are used in normal frame forwarding decisions, so therefore blocking states do not learn.
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