x460-G2 New VLANs stop at times

[IT_Guy]

Two x460-48p G2 switches comprise the stack (10.0.0.5). 'Default' & 'VOIP' (ID 1 & 4) VLANs have been in place for years & pass traffic over LAN, WAN & Internet without an issue.

Recently added 7 additional VLANs 'wifi-1', 'wifi-2', etc. In testing the new VLANs they pass traffic for a period, then suddenly all the communication on the respective VLAN stops. Meanwhile the 'Default' and 'VOIP' traffic continues to flow, uninterrupted.

Example: VLAN- 'Wifi-1' (ID 401) 10.101.0.1/24

A workstation with an Ethernet connection (10.101.0.20) on 'Wifi-1' successfully tests on LAN, WAN & Internet traffic for a period. Randomly, all traffic stops & during this time the workstation cannot ping 10.101.0.1, 10.0.0.5 (default route), or anything else downstream. At the same time 'Wifi-1' is not communicating, VLANs 'Default' & 'VOIP' continue to pass traffic with zero interruptions

What am I missing?

[AdrianO]

This has happened to me too in vlans where clients use dhcp. I´ve found that an inmediate solution is to delete the vlan completly and reconfigure it, this restores communications. Evidently it's not a valid fix for normal operations but useful in an emergency. 

[IT_Guy]

Hardware is running 30.7.2.1-patch1-58. While connectivity of the VLAN is down the following items have been validated:

• The route table remains correct (and does not change).
• The forwarding database still shows the clients in the correct location.
• There are no indications of port errors, port congestion, or qos-based discards.
• Logs do not show any indication of a problem.

[OscarK]

Spanning tree blocks the port/vlan ?