We are wondering if not having route entries in some of our switches (all Cisco WS-C3560-48PS switches) or not having a default gateway set could result in this issue. All these switches are setup for VOIP phones to connect to them for power (Poe) and allow computers to daisy chain off the phones - we have attempted to define two (2) vlans to accomplish this (voice and data). Attached are redacted config files for each switch named: SW0, SW1, SW3 and SW6. The configuration is that SW1, SW3 and SW6 all linked (previously) to SW0 via SFP ports (using 3 of the 4 available). In brief we set the uplink ports like this:
interface GigabitEthernet0/1
description UPLINK
switchport trunk encapsulation dot1q
switchport mode trunk
spanning-tree portfast
All the remaining Ports, usually 1-47 or 1-48 were setup like this:
interface FastEthernet0/2
description PC/PHONE
switchport mode access
switchport voice vlan 2
spanning-tree portfast
Our gateway (firewall) is 192.168.1.14 and our LAN is one subnet: 192.168.1.0/24 with the switches listed using IP's assigned using +10 so SW0 is 192.168.1.10 and SW3 is 192.168.1.13. The Voice circuit uplinks into the switches on port 48 of switch SW0 and the Cisco stack uplinks to our data switches at SW6 port 2.
The change...
About 12 hours prior to the problem we moved about 5 connections off of SW1 and onto other switches in the Cisco stack. Then, this morning (when the problem happened), we relocated the remaining network lines from SW1 to either SW3 or SW6 and then powered down SW1. It was at this point that some users on SW3 were lost connection and so we put SW1 back online and moved the users that came off it to their previous ports on SW1...however, SW1 SFP activity light did not flash anymore. We tried a different SFP cable and even tried the one remaining unused SFP port before giving up and deciding to setup port 47 on SW3 and SW0 as the trunk.
1) What do you think happened?
2) Do we need to add routes to our switches to avoid this issue?
3) Should we try disable/enable on the SFP port via a shutdown command - or is that a long shot?
4) Should we have spanning-tree portfast on our trunk ports or not? I've heard rationale for yes and no.
We are planning to take the SW1 to a new building and start setting up a skeleton LAN there before we move there.
