I’m having a very strange problem after upgrading two separate PTP links to 4.2. On occasion these PTP links will lose the wireless connection due to interference, someone putting a big rig in front of an antenna, birds, or whatever. No big deal in the past. In a few seconds they come back up and all was well.
Now, when the link is lost and comes back up, I can’t get ARP to pass between the devices on the either end of the link.
A couple other factors:
These are PTP links with the master in “Bridge” mode and the slave in “Station WDS” mode.
We are pushing multiple VLAN’s across the connection.
We have a separate bridge for each vlan, and a vlan interface for each vlan.
Sometimes it seems that ARP won’t pass on just one VLAN / bridge.
Then, the magic…
We log into winbox or telnet / ssh and things start coming back up. I haven’t been able to track down what exactly triggers the recovery yet. Sometimes it seems that looking at /int wireless registration-table print does the trick, or maybe it’s just a coincidence. Yesterday we were able to telnet into both sides (via the ethernet on both sides) and the traffic started passing on the wireless link before we even issued any commands.
These are RB411AH’s with R5H wireless cards. The EXACT configuration has been working fine for months on 3.X versions of RouterOS. Nothing has changed except the RouterOS version and key.
My gut tells me some sort of link recovery code is not being triggered automatically when the link comes back up, but instead it waits until something in the management interface forces a refresh. I wonder if this problem may be related to the reports of VPN’s dropping and not coming back up in 4.2?