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gunther_01
Premium
join:2004-03-29
Saybrook, IL

[Tech Ops] Conversion to a "smart" HP switch

We (tonight) upgraded an equipment rack and added a couple "smart" switches in replacing our old standard "dumb" switches.

In this process it seems that our newer, but inexpensive HP 2510-24 switches don't like to play nice for some reason. I defaulted them (since they were used) but am having an issue with what seems like the ports are VLAN'ed to some effect.

The system goes Image Stream router - Switch - NBM5 (ap WDS) - NBM5 (ClientWDS) - MT router all with GW's of the IS router and such. Previously it was Image stream (no switch) and so on.

We never had a problem with this senario previously. Now it seems that a client device within the correct subnet plugged in to the switch directly can access the NB's and the MT but nothing past the MT. But anything after the MT, can't access the NB's, but can the GW. It's the darned weirdest thing I have really ever seen. In some respects we run a pretty good network, it's been routed from the get go, and I have never had to deal with a smart switch that may or may not be causing me grief so I am quite perplexed right now (and tired as hell which doesn't help)

I had a similar problem with a new switch (tonight as well), same model, causing us problems on the public IP side of things. We couldn't get in to one of our servers thats 1:1'ed at the Image stream, but we could access one that was a direct public IP via the switch. Replacing that switch with a dumb switch and all was good instantly.

I have rebooted everything to clear ARP tables, and just about anything I could think of, including making sure no VLAN's were active on any of the ports (and maybe that is where I goofed, but that is defaults which should be correct IMO since we don't run VLAN's anywhere)

Does any one have an idea? I don't get it for some reason. And I don't feel that I am dumb at networking, or configurations.
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»www.wirelessdatanet.net



TomS_
Git-r-done
Premium,MVM
join:2002-07-19
London, UK
kudos:5

Re: [Tech Ops] Conversion to a "smart" HP switch

You can test pretty easily if its a VLAN thing by plugging a device into one port, and then moving another device between all remaining ports while running a ping. If there are no VLANs in play (or specifically, ports configured as access ports in different VLANs), you should be able to ping between the devices from all ports.

My next question is, while you might not run any VLANs on the switch, are any of the routers or APs configured to use VLANs in any way? Perhaps for the management interface?

Some "dumb" switches will pass anything that comes into them, including ethernet frames with VLAN tags, even if the switch doesnt "understand" them itself. But a "smart" (aka managed) switch will play by the rules with which it has been configured. This means that if any of your devices are sending any VLAN tags at all, the managed switch wont pass them unless it has configuration that explicitly allows it - which means you'd have to configure your ports as trunks and define the list of VLANs on the switch, and potentially even specify on a port by port basis what VLANs should be allowed to pass.


gunther_01
Premium
join:2004-03-29
Saybrook, IL
reply to gunther_01

The best I can tell nothing is using VLANs. In the MT I looked under switch>Vlan and there are none (which this MT box is fully routed on all ports, or should be LOL)

In the IS router I don't seem to find any devices that are labeled as such. By the looks of the wiki for IS, it should show vlans as a seperate device within the CLI.

What I am seeing digging a bit deeper is that the switch can't pass traffic itself past our MT router. It can however get past the IS going to the internet. The MT seems to not like something IMO. Traffic is going through it from customers, which makes it that much more weird. I'm going to bed though LOL
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»www.wirelessdatanet.net


gunther_01
Premium
join:2004-03-29
Saybrook, IL
reply to gunther_01

So what if the switch IP is in a management VLAN but nothing else is using VLAN's?

The switch sits between two of our key routers, the head end, and an upstream "in network" router. Both of which use RIP for the time being to auto route. The switch can't ping anything upstream within our network, but CAN ping Internet locations. Similarly, nothing upstream except the MT router, can ping the switch IP. Is this because of it being in the management VLAN by default? And if so, can that be removed easliy?

Still reading up on it, but any insite is helpful.
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»www.wirelessdatanet.net



Inssomniak
The Glitch
Premium
join:2005-04-06
Cayuga, ON
kudos:2

I dont understand.

A factory reset smart switch should act dayum near like a dumb switch minus what TomS said about it possibly stripping off vlan tags on egress ..

Ya might have to dive deep into the manual of that thing
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OptionsDSL Wireless Internet
»www.optionsdsl.ca


gunther_01
Premium
join:2004-03-29
Saybrook, IL
reply to gunther_01

Apparently..

It does read that all ports are untagged but are in VLAN1 on a defaulted switch of this model. I'm not sure exactly what the heck that means though unfortunately. My assumption is if the data isn't tagged then it isn't in a VLAN, but then they say all ports are in VLAN 1 at the same time. HUH?

Something about that's how the switch works, and you can't delete it.

They act deffective in some respects, but then I look at how some of the data works and some doesn't work and it seems like the MT router at our tower isn't processing things correctly because of it (whatever it is)

I have similar problems going the other way with traffic when we add the same model switch to our public side of our ImageStream router. Then traffic seems to not move anywhere for customers, but I am able to ping sites and such on the Inet.

I will make some more phone calls for some of our other proxy systems that this may be ticking off for some reason. But if you have any ideas, feel free.
Thanks,
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»www.wirelessdatanet.net


VCWireless

join:2010-11-17
Valley Center, CA
reply to gunther_01

Some smart switches come with the ports defaulted to not be a dumb switch but more of a work station port (don't ask me what the difference is), but mine wasn't working correctly out of the box.

However if you can log into the switch verify the port is setup for a switch and not work station mode.

Probably not the solution but figured I would throw it out there...


petecarlson

join:2004-11-06
Baltimore, MD

said by VCWireless:

Some smart switches come with the ports defaulted to not be a dumb switch but more of a work station port (don't ask me what the difference is), but mine wasn't working correctly out of the box.

However if you can log into the switch verify the port is setup for a switch and not work station mode.

Probably not the solution but figured I would throw it out there...

That would be access ports and not trunk ports. Could cause some weird issues.

Why not just console the switch and set all the ports to trunk ports and allow vlans 1-256 or something like that?

gunther_01
Premium
join:2004-03-29
Saybrook, IL
reply to gunther_01

It looks like nothing we have in place on this switch uses or has VLANs set up. BUT, the switch does place all ports in VLAN1 "untagged" status. I am going to try it in a couple days, but I think I can assign all ports to no for the VLAN and that should solve it I hope.

VLAN1 for all ports untagged is the default on this device it seems.
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»www.wirelessdatanet.net