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which configuration is correct, if either??

which configuration is correct, if either??

which configuration is correct, if either??

I hav two 2910al 48 port layer 3 switches. I want to have one switch as one vlan and the other switch as another vlan. I'm trying to work out which is the best way to connect the switches together regarding vlans. I have setup a trunk between the switches on ports 47 and 48 on both switches. I have enabled ip routing on the first switch.

On the first switch which contains the default vlan 1 and a vlan called vlan 2. All ports are untagged as default vlan 1 expect 47 and 48 which are untagged as vlan 2.
On the second switch which should contain the second vlan vlan 2. However the way the switch has been configured all ports are untagged and part of default vlan 1. There is no other vlan on there.

Or is this correct

On the first switch which contains the default vlan 1 and a vlan called vlan 2. All ports are untagged as default vlan 1 expect 47 and 48 which are untagged as vlan 2.
On the second switch there are two vlans. The default vlan 1 and a vlan called vlan2 all ports are untagged and are part of vlan 2.

The second one makes sense to be but I was wondering if the first one was ok because all ports are part of the one vlan so when packets hit 47 and 48 on the first switch they would not get tagged so when it goes to the second switch it doesn't need to have vlan 2 on it and can instead use the orginal default vlan.

Thoughts pleaseeee

RE: which configuration is correct, if either??

Either way, it sounds like you have chosen the first switch as your "main" switch, so maybe there is access to Internet or servers that go through that switch. Since you have enabled IP routing on the first switch, then you need to establish VLANs you are wanting to route on that switch. You will create those same VLANs on the second switch (same VLAN ID) and define the first switch as the default gateway. The port or ports (you can create a trunk group with multiple ports) you use to connect each switch together, you'll want to again mirror that config on both. You'll "tag" your created VLAN (VLAN 2 from your example) on both switches port or trunk that you established so that VLAN 2 will pass between the switches. You'll finally "untag" ports on whatever switch and/or ports you choose for that VLAN 2 as you mentioned... VLAN 1 happens by default until changed.

As a side note, you can set the first switch as "Commander" and the other switch as "Member" for stacking. You can stack up to 16 of these switches together and manage them via one IP address. http://www.hp.com/rnd/device_help/help/hpwnd/webhelp/HPJ4121A/configuration_stacking.htm

Hope that helps.

RE: which configuration is correct, if either??

Thanks for the reply Cajuntank,

this is quite a long reply Sorry

Yes you are correct that the first switch is the main switch which is connected to the internet etc..
The bit I am getting confused on is
If I can recap with a bit more detail so you don't keep having to reread my other post

First switch = core switch. Ip routing enabled on it connected to the firewall etc.. Port 47, 48 are in a trunk TRK1 and are part of a vlan, "vlan 2". It has an IP address assigned of and the two ports are Untagged (they are not part of any other vlan.) The rest of the core switches ports are part of the default vlan "vlan 1".

Second switch = Dis switch. Ip routing is not enabled it is connected to the Core by Port 47, 48 in a trunk TRK1 These ports and all other ports are part of the default vlan 1 so all ports are untagged. There are no other vlans on that switch. There is a ip address assigned to the switch for management and as IP routing isn't enabled then it will use the default gateway which is (the core switch Vlan2 address)

So I'm trying to work out if this is what is causing me to have packets drop and sql transport errors. Thinking about it as the ports 47, 48 on the core are only part of the one vlan "vlan 2"  they are untagged, the packets will not contain the extra tag bytes that are required if it was a tagged vlan and packets. So when it sends through to the other switch it should still work as normal??? Hence why the people (not me) that set it up have set it up without vlan2 to the second switch. I have tried changing it over so the second switch has a second vlan on it called vlan 2 and assigned all the ports on the switch to vlan 2. It didn't stop my problem with the packet losses and sql transport errors, but I would still like to know which is the correct way that this should be setup and what errors can happen from it's current config.

regarding the errors, I have another switch connected to core which is part of the default vlan and I get no transport errors on it.
I have so far replaced all the cables, network cards, moved points, tested on points that I know work. replaced the second switch. and thats the problem the only different is I'm on this other vlan.  
Can't see any errors in PCM+ either. In wireshark I can see lots of retransmission, loss of packets.

Any Ideas


RE: which configuration is correct, if either??

Bridging VLANs as you have on your 2 switches should not cause any errors. You may get log events telling you of a "VLAN mis-match" or something. You *should* change switch 2 so all ports are in VLAN2, just to make it simple and unambiguous.
Check your Trunk config to make sure it's all working properly, though. Disable one member of each trunk to see if it's any different.

RE: which configuration is correct, if either??

Sorry I have not responded till now, been in deep for the past couple of days in Polycom world. Have you checked something as simple as speed or duplex mismatch? Mismatches will cause lots of retransmissions and performance issues.
Also, what version of software are you on for the 2910al's? I had all kind of issues on mine with my iSCSI SAN and dropping packets on their posted rev (W14.49) on the website. Had to call tech support for them to send me an internal build (W14.65), once I got that loaded, life was good.

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