NETGEAR FVS338 FVS338 ProSafe VPN Firewall 50 Re ference Manual , B-6 System Logs and Error Messages, System Logs: WAN Status, Auto Rollover

v1.0, March 2008

PPP Logs

Message Nov 17 09:59:09 [FVS338] [wand] [LBFO] WAN1 Test Failed 1 of 3 times_

Nov 17 09:59:39 [FVS338] [wand] [LBFO] WAN1 Test Failed 2 of 3 times_

Nov 17 10:00:09 [FVS338] [wand] [LBFO] WAN1 Test Failed 3 of 3 times_

Nov 17 10:01:01 [FVS338] [wand] [LBFO] WAN1 Test Failed 4 of 3 times_

Nov 17 10:01:35 [FVS338] [wand] [LBFO] WAN1 Test Failed 5 of 3 times_

Nov 17 10:01:35 [FVS338] [wand] [LBFO] WAN1(DOWN), WAN2(UP),

ACTIVE(WAN2)_

Nov 17 10:02:25 [FVS338] [wand] [LBFO] WAN1 Test Failed 6 of 3 times_

Nov 17 10:02:25 [FVS338] [wand] [LBFO] Restarting WAN1_

Nov 17 10:02:57 [FVS338] [wand] [LBFO] WAN1 Test Failed 7 of 3 times_

Nov 17 10:03:27 [FVS338] [wand] [LBFO] WAN1 Test Failed 8 of 3 times_

Nov 17 10:03:57 [FVS338] [wand] [LBFO] WAN1 Test Failed 9 of 3 times_

Nov 17 10:03:57 [FVS338] [wand] [LBFO] Restarting WAN1_

Explanation The Logs suggest that the fail-over wa s dete cted after 5 attempts instead of 3.

However, the reason the messages appear as above is because of the WAN

state transition logic which is part of the failover algorithm. The above logs can

be interpreted as below. The primary link failure is properly detected after the

3rd attempt. Thereaf ter the algorithm attempts to rest art W AN and checks once

again to see if WAN1 is still down. This results in the 4th failure detection

message. If it is then it starts secondary link and once secondary link is up,

secondary link is marked as active. Meanwhile secondary link has failed once

more and that results 5th failure detection message. Please note that the 5th

failure detection and the message suggesting secondary link is active have the

same timestamp and so they happen in the same algorithm state-machine

cycle. So although it appears that the failover did not happen immediately after

3 failures, internally, the failover process is triggered after the 3rd failure and

transition to secondary link is complete d by the 5th failure. The primary link is

also restarted every 3 failures till it is functional again. In the above log, primary

link was restarted after the 6th failure i.e. 3 failures after the failover process

was triggered.

Recommended Action Check the WAN settings and WAN failure detection method configured for the

primary link.