Gateway MAC Address (GMAC)

The Link LB fails to balance outgoing traffic in singlemode.

Check that you attached all required interfaces to that VFI (attach out command). Also, make sure that you bound interfaces to the GMAC (gmac dev command).

The gmac TCP polling fails to pass through a firewall.

By default, the Link LB selects the first IP address that matches the GMAC subnet to use as a source IP for polling. Through a firewall, use the gmac tcpprobe command to fix a static source IP for polling and verify your firewall security rules.

Which destination IP and ports should I use for polling?

Polling is done by a TCP handshake. You should consider having two different destinations that are stable and up 24/7; such as internet route servers, major public search engines or mail services. Please note that it is considred best practice to have different destinations for different GMACs (don't use the same two destinations for all GMACs). Whenever we configure units we choose between our own servers, high-visibility websites and root DNS servers. 

If you wish to use our servers among your TCP polling destinations you can configure the following IPs and TCP ports in your GMACs.

Server 1 located in Montreal, Quebec, Canada

elfprobeca1.elfiq.com - 72.55.143.202 port 1148

elfprobeca2.elfiq.com - 72.55.148.108 port 1148

Server 2 located in Los Angeles, California, USA

elfprobeus1.elfiq.com - 66.152.169.66 port 1148

Server 3 located in Singapore, SG

elfprobesg1.elfiq.com - 203.76.174.62 port 1148

Should the Link LB always poll destinations to verify that the link is up?

With version 3.1.20, the feature gmac_true_traffic enable command stops polling when valid traffic passes through the link, polling is resumed when there is less than 5%.

My WI-FI or satellite GMAC is always disabled.

Because of the possible latency of those links, you should probably increase the polling time-out and threshold. The command is gmac probe.

I see the message : "1 (Alert) gmacX [Desc], is considered unstable (link flap), admin disabled [link down]" in my logs. What does this mean?

GMAC link flap is declared when a GMAC has been repeatedly UP and DOWN and we have reached 5 instances of the GMAC being declared down over the last 60 minutes. When this happens a message will be logged and the GMAC be disabled for the next 60 minutes. Once the 60 minutes period is elapsed the GMAC will be re-enabled automatically by the Link LB. This protection is to prevent sessions to be changed of link every few minutes (and impact users) when a link is very unstable and requires ISP intervention.