Help adding in new VLAN for 4600 phones

[lslebodnik]

I am working with a Definity G3 here. 4600 IP Phones work fine on default vlan, but when I try to add an additional vlan they hang at discovering forever. What is needed for the phones and PBX to work with additional vlans. It is not practical to have the PBX and phones on the same vlan either. The phones are able to get config from DHCP and do find and download the settings from tftp no problem. Also a laptop works fine on this VLAN. What might I be missing? I have looked over a lot of PDFs and they are exceedingly vague to someone who doesn't do this stuff every day. Data switches are HP ProCurves.

 

[boristhespider2]

When you say that it is not practical to have the PBX and the phones in the same vlan ....why ??? if they are on the same physical geographic site it makes total sense to have Voice on vlan 1 and data on vlan 2 , could you explain your reasoning further as I don't want to miss something obvious.

 

[mattKnight]

>When you say that it is not practical to have the PBX and the phones in the same vlan ....why ???

best practice (from a network point of view) is to not have a host network bigger than a /23 (approx 500 hosts). If you need more than 500 handsets on a site, better to that 3 VLANS (each /24 mask) and use the L3 core switch to route between them if required.

> but when I try to add an additional vlan they hang at discovering forever
Routing between handset VLAN and PABX VLAN (or reverse)
Are you sure your DHCP scope is correct?

Take Care

Matt
I have always wished that my computer would be as easy to use as my telephone.
My wish has come true. I no longer know how to use my telephone.

 

[lslebodnik]

I really just need to know the low level explanation of how to get a vlan to work with 4600 series phones and a G3. We are only talking 16 phones here, not a giant infrastructure. The old setup was a t-1 connection to remote site using a Cisco 17XX router. The router seems to have done some sort of gateway service for the phones because the PBX references it. The new setup is a true point to point fiber link. As such there is no Cisco gateway in the middle, it is treated just like any other port. I still need to vlan that site to a different IP range though. That is where the problem comes in. PCs work fine in the new VLAN but phones will just discover forever. The phones will get DHCP and the TFTP download, but they will never connect after that. Does that make it clearer?

 

[kyle555]

Maybe this might help
1.Phone boots, sends DHCP untagged on native VLAN
2.DHCP replies like normal, but also with option 176 that should say L2Q=1,L2QVLAN=1234 for VLAN 1234
3.Phone drops native VLAN IP, tags a DHCP request with VLAN 1234
4.VLAN 1234 replies with option 176 MCIPADD=10.10.10.10,TFTPSRVR=10.10.10.11

TFTPSRVR could just as well be HTTPSRVR

The phone will request tftp or

http://10.10.10.11/46xxsettings.txt,

and /46xxupgrade.scr

Those files have settings and upgrade scripts, but are optional, and the only thing you absolutely need to make a phone register is MCIPADD=10.10.10.10, which if you're on a G3 without Linux servers, would be the IP of a CLAN board that is allowed to be a H323 gatekeeper.

If your CLAN is in slot 1a05, do "change ip-interface 1a05" and make sure it can be a H.323 gatekeeper and allow phones to register, as well as ensuring it has a default gateway specified to it can reply outside whatever subnet it is in.

I think that last part about CLAN gateway might be most relevant if for as long as your system has been around you've been using 1 subnet for the CLANs, Medpros and phones - something as simple as a default gateway on your CLAN and Medpro cards would have been totally irrelevant until now if traffic never left a single /24 segment.