ProCurve Switch with ip address-helper

[Tux2013]

Hi!

Im looking for a HP layer 3 switch where I can setup multiple VLANs which are routed to a single DHCP server. Normally, one would use a ip address-helper for this function imho. Searching throught HPs online database of switches, I was somewhat confused by the naming of the layer levels.

As the company I am working for has a limited budget, I searched for the cheapest solution first:

Here are my candidates:

HP ProCurve  V1910-16G 16 Port

&

HP ProCurve Switch 2910al-24G

Now I know that the V1910-16G is a layer 2+ switch that supports static routing, but does it also support the ip address-helper for the VLANs? IMHO this should be the same thing, right?

If it doesn't, I will likely have to go with the 2910al-24G, which costs aroung 5x more here in Switzerland.

Thanks

Tom

[Fredrik Lönnman]

In Comware-world ip-helper is called dhcp relay. According to this user guide, the V1910 does it: http://bizsupport1.austin.hp.com/bc/docs/support/SupportManual/c02965327/c02965327.pdf 

[Tux2013]

Hi Fredrik,

Thanks for the answer! Can I assume that PXE traffic will also be forwarded using the dhcp relay (same server)? Sorry I didn't find any documentation regarding PXE in the file you linked, nor using google.

Thanks

Tom

[Fredrik Lönnman]

I haven't tried myself, but I'm pretty sure it will work.

[Pete W]

Is L3 functionality important to you (i.e.. do you actually need to route on this switch)?

Simply setting up multiple VLANs with IP helpers can be achieved on most of HP's L2 ProCurve fleet, and I often use the 2510Gs for this. However if you need really need IP routing, then certainly all of the ProCurve L3 switches support IP helpers.

Pete

[Tux2013]

Hi Pete

Are you sure you meant the 2510Gs? I have a 2510G-24 lying in front of me and the switch doesn't accept the ip helper-address or the dhcp-relay command...

Thanks

Tom

[Pete W]

Appologies, I was incorrect in stating that the 2510G can support IP helpers, however it is still capable of supporting multiple VLANs (L2 Only).

Even with the above mistake, I suppose the original querstion still stands. Do you need L3 routing on your new switch - or is an extension of an existing network where routing is already taken care of?

Regards,

Pete

[Richard Litchfield]

Here's an extract from a ProCurve 5400zl switch. Config will be almost the same for 2910, 3500, 3800, etc

vlan 30
   name "Wireless"
   untagged A1,B7-B8,B21
   ip helper-address 172.20.100.69
   ip address 172.20.30.1 255.255.255.0
   ip igmp
   ip rip 172.20.30.1
   exit

 The key element is "ip helper-address". Point that to your DHCP server with the relevant scopes set up and off you go!. Works fine with PXE, just add another line with the PXE server IP address.