i am a networking guy for many, many years but a newbe to firewalling and ipsec. Currently i am working on an ipsec connection between an ASA 5510 on my side and a fortigate box at another location. Looks fine so far , ipsec is established in tranport mode. When i ping a server behind the fortigate the pings run fine at first but soon latency starts to increase. When it reaches about 2 sec it suddenly drops back to normal and the whole thing starts again. This repeates to infinity .... The same happens the other way round.
Even your continous PING is random, I guess this isn't a MTU issue. I would love to blame Fortigate FW for this, as I hate non-Cisco products but then again you might never know, it could be the Cisco ASA 5510 that's causing this. I'm assuming your Internet/WAN connection is good. Perhaps, this Cisco document maybe of help https://supportforums.cisco.com/docs/DOC-4971
Even your continous PING is random, I guess this isn't a MTU issue. I would love to blame Fortigate FW for this, as I hate non-Cisco products but then again you might never know, it could be the Cisco ASA 5510 that's causing this. I'm assuming your Internet/WAN connection is good. Perhaps, this Cisco document maybe of help https://supportforums.cisco.com/docs/DOC-4971
