Curious VLAN and differentiated services traffic with new TV
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@Derelict said in Curious VLAN and differentiated services traffic with new TV:
Cisco has some settings that manipulate VLAN tags on mirror ports:
I don't know what tags it would manipulate, as I don't have any VLANs configured on this switch.
BTW, I'm more used to the term mirror, rather than span, as I started doing this sort of thing on Adtran gear, where it was called port mirroring. It's also called mirroring on both my Cisco and TP-Link switches. In fact, until recently, on another thread, I had never heard of span in this application. In my earlier experience, "span" referred to span lines, which carried T1 signals over significant distances, through the use of repeaters.
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No idea, man. I don't have one of those switches.
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But there stil is the default vlan 1.. you can not get rid of it.. you can just change the default.. I changed my default vlan to 9 but vlan 1 is still there, even if not used.
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@johnpoz said in Curious VLAN and differentiated services traffic with new TV:
Here check out this thread - this is what your seeing right?
https://community.cisco.com/t5/small-business-switches/mirror-vlan-tag-not-stripped/td-p/2272832/page/2"I can see this issue on SG200-8, I think it's not a bug, but an enhancement. For TX packets, by default they will be added a dot1q tag. "
If reading right, got around it via doing spans of just the rx on the 2 ports vs tx and rx on 1 port.
Could be. I'll have to check further. I just don't recall seeing that before, though I wasn't looking. Regardless, I wouldn't expect a tag to be added. What would happen if there were already 2 tags (QinQ). I have worked on networks where that was used.
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Your dest port on the mirror can not be a member of a vlan. All tags should be stripped going to dest mirror port.. Way I read that thread (really quick) is that is "feature" of adding tag to the tx traffic that is sent to the mirror port.. I think the suggestion of just using 2 rx sources would be quick work around for the "feature" ;)
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Have to ask Cisco.
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@johnpoz said in Curious VLAN and differentiated services traffic with new TV:
Your dest port on the mirror can not be a member of a vlan. All tags should be stripped going to dest mirror port.
I would think that a mirror should duplicate the original. As I mentioned, I have worked on systems where QinQ is used. It would be nice to be able to see the tags when working on it. On my TP-Link switch, I use port based VLANs to keep the monitor port separate from the traffic ports. I'll have to do some testing with both, when I get a round tuit.
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@Derelict said in Curious VLAN and differentiated services traffic with new TV:
Spanning Tree Protocol (STP)
I have certainly seen spanning tree on mirror ports. In fact, they became so annoying I created Wireshark filters to block them. On my home network, my PVR thinks it's the root switch.
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@johnpoz said in Curious VLAN and differentiated services traffic with new TV:
adding tag to the tx traffic that is sent to the mirror port
It appears to be the receive side, not transmit.
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@JKnott said in Curious VLAN and differentiated services traffic with new TV:
TP-Link does something better than Cisco!