Configuring vLan HP 2530-24G

[Eirualmac]

Hello all -

I've inherited the management of our (very) small network.  Our main switch houses most of the pc (18) & server (1), 1 port is pbx system, and another port is connected to firewall to internet. The switch has designated vlans (3rd oct.) 1 = data, 2 = phones, 3 = wifi (no wifi ap's are connected, they are all connected to their own switch, that connects to firewall, too). The pbx I have no control over, however, it requires internet (backup alarm). I do not believe it has been configured for voip, although the phones themselves have IP capability. (I believe the last person has configured all as analog system).  This network has been in place for a couple of years. The person who is managing the pbx is reporting their pc (on vlan1) is no longer able to reach the pbx to manage it (aparently it had been working fine & just "stopped"). The pbx has an ip adress of 192.168.1.99, where our network is 10.42.1.0. The individual states that if he changes his pc's address from the 10.42. to 192.168, he is able to reach the pbx (using web interface), but he cannot get out to internet. He states that he never had to change his ip address before, and he could reach internet & the pbx and the pbx used to be able to reach internet (alarm).  As I don't know what "happened", I've recommended to the individual to update the pbx to an address to co-inside with the designated ip from the switch (10.42.2) for phones. I am sure I probably should not have told him to do that, and am probably missing something very obvious to all you guru's out there.  I'm old school networking, retired and volunteering for non-profit, so I'm out of date (be kind).

My questions are many, but will start with any troubleshooting ideas you could share I would appreciate, and, with the vlan already indicated on the switch, when the pbx ip is changed, how will a pc from vlan 1 be able to reach vlan2 to manage the pbx?  What should be in place (configuration of switch should I verify) to permit?

[Vince-Whirlwind]

You need to list all your VLANs, the subnet associated with each one, and the router address for each one.

It sounds like your PABX and your desktop devices are in different subnets but patched to the same VLAN.
Either re-address the PABX to the correct subnet for the VLAN it is in, or, reconfigure its switchport to the correct VLAN for the subnet it is in.

Making the list I described should make the issue obvious.