GRE tunnel performance SLA

[BensonLEI]

Hi, guys,

I am using Fortigate 400E, 600E with FortiOS v6.4.2 and V6.4.4. For some reasons, my company perfers GRE tunnel.

It is found that the poor performance SLA of the GRE tunnel between two fortigates  ( often some percentage of packet loss often found, while the internet lines are running well - no packet loss ), any advice, thx a lot ?

Any article/doc to fine tune the GRE tunnel parameters/attributes ?