Please find few more updates about how fast an interface comes to forwarding state:
STP(pvst or iee):
-----------------------
Access Port without portfast/edgeport enabled. -- 30 sec (Initialize the port, listening to learning 15sec, learning to forwarding 15sec, total 30sec.)
Access Port with portfast/edgeport enabled. -- less than a sec (initialize stp on the port, then jump to forwarding)
Trunk Port where another Cisco Switch is connected which is also running STP. -- 30sec (listen to learn and learn to fwd)
Direct Link Failure without uplinkfast -- recovery is 30sec.(pkt drops)
Failed Direct Link restored without uplinkfast -- recovery is 30 sec. (pkt drops)
Direct Link Failure with uplinkfast -- recovery is less than a msec. (no pkt drops)
Failed Direct Link restored with uplinkfast -- recovery is 35sec (2*Fwd Delay + 5 sec (to converge other protocol like etherchannel, etc..)) with no pkt
drop
as soon as the actual (previous) link comes up, it goes to listen, then after 300 msec, it goes to root port delay timer and blocking state. Then after 35
sec... it goes to Root Port (Forwarding state).
Indirect link failure without backbonefast -- recovery is around 47 sec. (17-20 sec for max-age timer, 2*fwd_delay listen, learn, fwd.)
MM:SS:Msec
09:10:002 -- Heard Root
09:27:414 -- Listen
09:42:413 -- Learn
09:57:413 -- Forward
Indirectl link failure with backbonefast -- recovery is 30sec. (2*fwd_delay listen, learn, fwd.). Excluding max-age timer, instead sends and rcv RLQ
within 16 msec.
31:35:320 - Heard Root
31:35:346 - Listen
31:50:346 - Learn
32:05:346 - Forward
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802.1w (Rapid PVST+):
-------------------------------
Access Port without portfast/edgeport enabled. -- 30 sec. (Initialize the port, sends (18) proposal and if no reply, then the port will be up)
Access Port with portfast/edgeport enabled. -- less than a sec (initialize stp on the port, then goes to designated)
Trunk Port where another Cisco Switch is connected which is also running rapid-pvst+ -- 2.7 sec...
Trunk Port where another Cisco Switch is connected which is running pvst --- 30 sec.(Time is high due to absense of proposal/aggrement)
Direct Link Failure -- recovery is less than a sec. - with no pkt drops.
Failed Direct Link Restored -- recovery is than 2 sec with no pkt drops.
Indirect Link failure.. -- recovery is less than a sec..with no pkt drops.
Indirect Link failure recovered..... -- recovery is less than a sec..with no pkt drops.
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802.1s (MSTP):
--------------------
Access Port without portfast/edgeport enabled. -- 30 sec. (Initialize the port, sends (18) proposal and if no reply, then the port will be up)
Access Port with portfast/edgeport enabled. -- less than a sec (initialize stp on the port, then goes to designated)
Trunk Port where another Cisco Switch is connected which is also running MSTP. -- 2.7 sec...
Trunk Port where another Cisco Switch is connected which is running rpvst+ -- 3.5 sec...
Trunk Port where another Cisco Switch is connected which is running pvst --- 30 sec.(Time is high due to absense of proposal/aggrement)
Direct Link Failure -- recovery is less than a sec. - with no pkt drops.
Failed Direct Link Restored -- recovery is than 2 sec with no pkt drops.
Indirect Link failure.. -- recovery is less than a sec..with no pkt drops.
Indirect Link failure recovered..... -- recovery is less than a sec..with no pkt drops.
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Thanks,
Thiyagu Ganesan.
