02-03-2021 01:15 PM
I've created 2 VLAN's (200,400) for data and voice on 2 independent switches
The data switch is connected to the X0 port on the firewall and a Windows DHCP server where all users receive IPs.
The voice switch is connected to the X3 port on the firewall and all phones receive DHCP through the firewall.
When I try to uplink to a switch (LAG from each switch data and voice) I receive DHCP only from data and not from voice
Am I doing something wrong?
02-03-2021 02:48 PM - edited 02-03-2021 02:50 PM
I suspect that VLAN for voice is block toward FW when you use LAG,
can you check this point.
also connect PC instead of phone and assign IP and ping FW
02-03-2021 02:53 PM
When I use static IP I can reach the firewall. But phones need to get DHCP to provision.
02-03-2021 03:30 PM - edited 02-03-2021 03:34 PM
Hello
If the dhcp server resides in vlan 200 then on the X1 port of the FW add an helper address for the dhcp server and make sure both vlans 200 data-400 voice are created on the small office switch.
Lastly place each port connecting to the upstream switch's in their respective vlan
02-04-2021 12:56 AM
Just an update, if I uplink to another brand i.e HP Procurve, everything works fine
02-04-2021 02:41 AM
you mean replaced cisco with HP ?
02-04-2021 02:51 AM
Yes, I replaced the switch in the small office with HP.
Switch1 (SG550) has V400 tagged connected to Switch 3 (HP) on a V400 tagged
Switch2 (SG550) has V200 tagged connected to Switch 3 (HP) on V200 tagged.
If I connect to an untagged V200 on switch 3 I can get a DHCP, and if I connect to an untagged V400 on switch 3 I also get a DHCP.
The same scenario, if Switch 3 is an SG550 I can only get DHCP either from V200 or V400, whatever I connect first
02-06-2021 11:39 AM
If I get full understand the issue here,
LAG to two dummy SW impossible
why
two SW need to be stackable or VSS or vPC
Now
SW that LAG to two SW have STP issue and Etherchannel Issue.
Instead of
use access link between SW data and SW using VLAN data
use access link between SW voice and SW using VLAN voice.
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