Grandstream phone gets IP from wrong VLAN on Cisco 2960x

[bschmitz26]

Installing new IP phones; Grandstream GXP2135 / GXP2170 with 3CX on-premise server through 2-Cisco 2960x switches with a Watchguard M370 firewall.

Phones are connected to Sw2 ports 11-15 as Trunk ports with VLAN 1 and 50.

 - VLAN 1 - trusted Pc network; xxx.xxx.115.1/24. Pc's are planned to be connected to the phones.

 - VLAN 50 - trusted phone network; xxx.xxx.50.1/24

3CX switch is connected to Sw2 port 10 as Access port VLAN 50

Watchguard Interface 2 - VLAN interface as tagged VLAN 50 connected to Sw1 port 43 as Trunk port with VLAN 1 and 50.

- WG Inf2 doing the DHCP for VLAN 50 with xxx.xx.50.100 - xxx.xx.50.199

Sw 1 connected to Sw2 via port 48 on both set at Trunk Port with VLAN 'ALL'.

The problem I'm having is my phones are pulling IP add's from my VLAN 10 (xxx.xx.10.1/24).

The 3CX switch has a static VLAN 50 IP so the phone aren't connecting with the server.

I can't figure out how the phones are getting a VLAN 10 IP address.

I have 5 VLAN's setup, Trusted Pc network and WiFi SSIDs and they've been working just fine, so I'm thinking it's my Voice IP setup or not setup that I have wrong.(?)

I'm not a Cisco specialist and this is a first time IP phone setup for me.

I haven't mastered CLI so I use the Cisco Network Assistant, if that's an issue.

[Georg Pauwen]

Hello,

first of all, you need to run LLDP on your Cisco switches:

Sw1(config)#lldp run

Also, the Grandstreams need either option 150 or 132. How is the DHCP scope for the voice Vlan configured ?

Typically (depending on the switch model and IOS version), the switchports would need to be configured like this:

switchport mode access
switchport access vlan X
switchport voice vlan 50
spanning-tree portfast

[bschmitz26]

@Georg Pauwen 

Thank you for your reply!

As I stated before I'm not CLI savvy, I use the Cisco Network Assistant, could you explain how I run those commands or translate in CNA terms? 

DHCP scope? Not sure what you mean by that. 

I don't have any special settings in my DHCP for my Voice VLAN 50, I wasn't given any special instructions from my phone vendor. 

I looked at my DHCP options and 150 is a predefined option, it's asking for a "value"; something I should get from Grandstream?

[Georg Pauwen]

Hello,

to be honest, I don't even know if CNA lets you configure all this. The command line is not difficult, it is going to be almost impossible to assist you without you having access to the CLI.

[bschmitz26]

@Georg Pauwen 

I do have access to the console via Putty.

CNA tells me telnet is disabled.

I ran 'lldp run' on Sw1(config) 

What command(s) do I need to enable Telnet so I can access it through CNA w/o using the console?

I appreciate any help you can lend.

brad

[Georg Pauwen]

Hello,

you don't need TELNET if you have console access through PUTTY. What does the prompt show ? Does it look like this:

Router>

or 

Router#

[bschmitz26]

Hostname#

[Georg Pauwen · Accepted solution]

Hello,

that's good. First of all, make sure LLDP is running:

HOSTNAME#conf t

HOSTNAME(config)#lldp run

Then, access the individual interfaces, e.g.:

HOSTNAME(config)#interface GigabitEthernet0/1

and enter the lines below:

HOSTNAME(config-if)#switchport mode access
HOSTNAME(config-if)#switchport voice vlan 50
HOSTNAME(config-if)#spanning-tree portfast

[bschmitz26]

@Georg Pauwen 

Thank you for those commands.

That worked!

Now, I just have to make sure LLDP is running on the switch and then run those commands on each Interface Port that's going to have an IP phone plugged into it?

When this install is completed, I'll have 6 Cisco switches in 4 different buildings (same campus area). Will I need to connect to the console port on each switch to make these changes?

Would it be to my advantage to enable Telnet on these switches for future changes?

[Georg Pauwen]

Hello,

--> Now, I just have to make sure LLDP is running on the switch and then run those commands on each Interface Port that's going to have an IP phone plugged into it?

Exactly.

Usually, the switches should have a management IP address that you can Telnet to, rather than physically connecting to the individual devices. The IP address is typically assigned to Vlan 1 (which actually is not good practice, but most often done).

[bschmitz26]

Yes, we have an IP assigned to VLAN1 but I cannot connect to it...

TELNET and PUTTY tell me 'connect failed'.

TELNET within CNA tells me the Telnet client is disabled.

Is that something I need to run from the Console to "enable"?

[paul driver]

Hello

---

@bschmitz26 wrote:

Phones are connected to Sw2 ports 11-15 as Trunk ports with VLAN 1 and 50.

 - VLAN 1 - trusted Pc network; xxx.xxx.115.1/24. Pc's are planned to be connected to the phones.

 - VLAN 50 - trusted phone network; xxx.xxx.50.1/24

3CX switch is connected to Sw2 port 10 as Access port VLAN 50

Watchguard Interface 2 - VLAN interface as tagged VLAN 50 connected to Sw1 port 43 as Trunk port with VLAN 1 and 50.

- WG Inf2 doing the DHCP for VLAN 50 with xxx.xx.50.100 - xxx.xx.50.199

Sw 1 connected to Sw2 via port 48 on both set at Trunk Port with VLAN 'ALL'.

The problem I'm having is my phones are pulling IP add's from my VLAN 10 (xxx.xx.10.1/24).

The 3CX switch has a static VLAN 50 IP so the phone aren't connecting with the server.

I can't figure out how the phones are getting a VLAN 10 IP address.

I have 5 VLAN's setup, Trusted Pc network and WiFi SSIDs and they've been working just fine, so I'm thinking it's my Voice IP setup or not setup that I have wrong.(?)

---

it could be vlan hopping is occurring, Do you have a native mismatch on the trunks and any sub interfaces, 

[bschmitz26]

@paul driver 

Thanks for that input.

I check all my ports and Vlans and they are all at Native 1. 

brad