G+_Adam EL-Idrissi Posted February 14, 2015 Share Posted February 14, 2015 Simple question,Can you use a combination of unmanaged and managed switches with vlans and link aggregation? Link to comment Share on other sites More sharing options...
G+_Eddie Foy Posted February 14, 2015 Share Posted February 14, 2015 interesting question. I could see reasons why it would both work and not work. following :) Link to comment Share on other sites More sharing options...
G+_Mikael Eidsvaag Posted February 14, 2015 Share Posted February 14, 2015 Unmanaged switches are also called “dumb” switches, in theory you can’t have more than one vlan on the same “dumb” switch. However, you can have one smart switch that you connect 2 “dumb” switches into, the two switches can have different subnets/vlans but they can talk to each other. Link to comment Share on other sites More sharing options...
G+_Ben Yanke Posted February 14, 2015 Share Posted February 14, 2015 For those familiar with audio, you could also think of unmanaged switches as headphone splitters, whereas managed switches as aux outputs on a mixer. You can do different things with all the different aux outputs, but if you hook up an unmanaged switch anywhere, it will just repeat the same things along, no change. And yes, you can use unmanaged switches alongside managed, if you keep this in mind. Link to comment Share on other sites More sharing options...
G+_Ben Reese Posted February 14, 2015 Share Posted February 14, 2015 Seems like when I was researching this a while back, most unmanaged switches would strip the VLAN info of anything that passed through it, though some would pass that along. That could be wrong though. Link to comment Share on other sites More sharing options...
G+_Ben Yanke Posted February 15, 2015 Share Posted February 15, 2015 I don't believe that is correct...I'm not sure why it would break it, there's nothing to "strip." It's simply the main managed switch acting with some primitive routing functionality, and not linking certain ports (or in other words, acting like two or more discreet switches). If you have 2 ports that are their own vlan, if you add an unmanaged switch to that, it would only add more ports to the vlan, not break anything.? Link to comment Share on other sites More sharing options...
G+_Ben Reese Posted February 15, 2015 Share Posted February 15, 2015 Well, I think there actually is something that identifies the VLAN that each packet belongs to (http://wiki.wireshark.org/VLAN), but the issue is whether or not the switch cares the the packet has extra data in the header. Looking into it a bit more, I found this: http://blog.thelifeofkenneth.com/2014/03/pushing-vlan-tags-through-unmanaged.html. It turns out all the unmanaged switches he tested processed larger packets they actually had to. This could be a security risk waiting to happen, but it also should allow the VLAN tagged packets to pass on through. Link to comment Share on other sites More sharing options...
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