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one_co_il
New Contributor

Detect Non Stable WAN with Link monitor

Hi

I setup Link monitor for redundant Wan connections. It's working great when WAN line is down 

but if a WAN line is not stable and getting 40% packet lost its not taking it down.

probably because its not getting 3 bad ICMP in a row

is there an other setting that i can configure for detecting non stable Connection?

3 REPLIES 3
Toshi_Esumi
Esteemed Contributor III

There might be something different in SD-WAN config to specifically detect packet losses, which I'm not familiar with. But again it would be likely using the same ping mechanism the link-monitor uses.

If the packet loss rate is consistently 40%, the probability is your link-monitor ping packets would be lost 40% as well. In reality those drops don't happen exactly in the same sequence all the time like !!!!!!....!!!!!!....!!!!!!!....(18 successes/12 failures) and so on. But likely something like !!..!!.!!..!!!.!!!!....!!..!!!(18 successes/12 failures).

I think you can adjust the interval shorter from the default 5 sec, and less failtime from the default 5 times to catch those failures to trigger a failover. Most difficult part is you can't test until 40% packet loss ready happens.

 

neonbit
Valued Contributor

SD-WAN is the way to go, you can create a SLA rule to say if ping drops are less than 40% then goto secondary link.

one_co_il

neonbit wrote:

SD-WAN is the way to go, you can create a SLA rule to say if ping drops are less than 40% then goto secondary link.

It seems that the Link status configuration of SD-WAN are the same as Link monitor

ICMP fail for X times at X intervals  

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