WAN connection dropping for a few seconds (10-20 times a day)

[#1]

Hi, We have a Fortigate-50b in a small office configured as a simple NAT router. 10 to 20 times a day the connection on the WAN side drops for a few seconds. In the event log I see these events coming up each time: 3/05/2011 6:09:16 information system 36870 interface-stat-change Link monitor: Interface wan1 was turned up 3/05/2011 6:09:15 information system 36870 interface-stat-change Link monitor: Interface wan1 was turned down I couldn' t find anything in the KB of Fortinet. Anyone? Thanks in advance... Vincent

[#2]

There' s always 1 or 2 seconds between the down event and the up event, never longer. I found this in the high availability handbook: These log messages, recorded by the primary unit, show the monitored port1 interface failed or was disconnected and the primary unit becoming a subordinate unit: 1 2010-01-14 16:59:39 log_id=0100020099 type=event subtype=system vd=root pri=information action=interface-stat-change status=DOWN msg= " Link monitor: Interface port1 was turned down" The id is not the same, but the message is. Could be a problem with the cable or modem? I' m going to plug out the modem a few seconds before I close off for the weekend. That' s our ISP' s answer to every connection problem ;-) Then I will see tomorrow if the event is coming back. If not: Yeeey! If yes, I' ll try patch 6. Or maybe test the cable one way or another? In the meanwhile, I opened up a ticket with Fortinet...

[rwpatterson]

Are you using High Availability?

[#4]

Problem solved! There was a distortion on the cable somewhere outside the building. ISP solved it with a new cable...