VLAN to act like a HUB ( no mac learning )

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XoS, I wish to have a vlan act like hub in the MAC learning sense, I just wish it to flood all traffic to all ports in that vlan. this is because this vlan is reciving some mirrored traffic from a another vendors equipment and I have a remote packet capture device.  the trunk links are shared so I cannot change the learning on a ports basis. really I need to turn of mac learning for a vlan.
Thanks in advance, 
Simon
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simon bingham

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Posted 1 year ago

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Mrxlazuardin

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Hi Simon,

As long as I know, mac learning is port based, not vlan based. FDB uses MAC learning for choosing which port such data should be forwarded to. Please refer to following URL.

http://documentation.extremenetworks....

Best regards,
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Mrxlazuardin

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I think following statemen on that URL can suite your requirement. So just disable learning with forward-packets option to all ports belong to such VLAN.

If unicast, multicast, and broadcast packet from a source address is not present in the FDB , the packets is flooded.
(Edited)
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simon bingham

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Thanks for your response, I think this issue is if you are mirroring to vlan ( from some other device ) the port will see both the source and destinations, so in switch logic it will think " both those addresses are off that port " so I do not need to forward it all.
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OscarK, ESE

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You could use an ACL with as action redirect-vlan, then it will flood all matched traffic in that vlan.
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simon bingham

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Thanks Oscar


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Michal Rz

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There is option 'remote-mirroring' when you configure vlan and it does exactly what you need.

https://gtacknowledge.extremenetworks.com/articles/How_To/How-to-configure-remote-mirroring
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simon bingham

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Hey thanks for that response, I often wondered if this  remote mirroring is simply a vlan with learning turned off I bet it is.
Juniper as a "no-mac-learning" command, this may be the equivalent
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Michal Rz

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from concepts guide:
Configuring the Intermediate Switch
Reserve a VLAN with the remote-mirroring keyword in all the intermediate switches for remote mirroring. When you enable mirroring with remote-tag 1000, you need to reserve a VLAN with tag 1000 in all the intermediate switches for remote mirroring. The remote mirroring VLAN in the intermediate switches is used for carrying the mirroring traffic to the destination switch. The ports connecting the source and destination switches are added as tagged in the intermediate switches.

Another way to configure a remote mirroring VLAN is to create a normal VLAN and disable learning on the VLAN. IGMP snooping must be disabled on that VLAN for you to remotely mirror multicast packets through the switch.
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simon bingham

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A little belated on my part, but thanks for your answer.