EXOS: STP on MLAG ports

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Are there any plausible reasons why STP is not possible on mLAG ports ?

For a current network project is would be very useful if i can use STP on core layer links (where 2 links are bonded with mLAG).
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M.Nees, Embassador

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Posted 3 years ago

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André Herkenrath, Employee

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Hi Matthias,

You should only use one L2 Protection Protocol at a time. Therefore it's either MLAG or STP

Best Regards
André
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M.Nees, Embassador

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Hi Andre, for my current project is would be a need to do that. If you see the mLAG only as a Link Aggregation point is not plausible why this cannot be part of STP (and forward BPDUs).
This aspect is the core of my question!
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Mel78, CISSP, ECE

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Your core question is contradicting. If you want STP, 1 link will always be blocked.

No load sharing.


I suggest you go Software-Controlled Redundant Port and Smart Redundancy.

STP is so slow to converge, typical 40 secs !!!. RSTP is 8 secs.

And during convergence, your whole network will be BPDU storm everywhere.

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Carsten Buchenau

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Matthias, to be clear: If you do not configure STP at all, BPDUs are still being forwarded, also through MLAG links. This is because for the EXOS Switch this is just standard Multicast traffic.

See here for a similar discussion:
https://community.extremenetworks.com/extreme/topics/extreme-summit-x670v-stp-disabled-by-default-it...
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M.Nees, Embassador

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Hi Carsten,

your are right i could only enable STP on the specific switch (not on all switches!) with the 2 regarding links (which on have to be blocked).

in my lab environment i use currently software redundant port which works fine.

Regards