Hello everyone,
I am dealing with a packet loss issue with Site-to-Site VPN this issue is causing havok on the voip phone system.
Three Sites
Site A - HQ
Site B
Site C
A has a vpn tunnel to B and C
B and C are also connected to a VPN Tunnel
the vpns are IPSEC using IKEv1
when I ping anything dealing with an outside ip (Google etc or even the external IPs of the ASA’s there is no packet loss from any of the sites.
the moment I ping an internal IP from one of the other sites (it doesn’t matter which site to which site) it will go good. Then drop then good then drop many times in a row then go good.
there is no repeatable pattern
Site A - 5506
Site B - 5505
Site C - 5505
I have messed with the TCP options to increase the allowable packet size and that didn’t help.
I have the DF bit to Clear
the interfaces are all all set to full Duplex and the appropriate speed.
each of these fire all’s are connected to an edge router that provide the SIP trunking.
Each location has fiber. This problem was occurring before the fiber.
the problem that is happening is the VOIP appliances at each of the satellite sites are having an excessive packet loss when connecting to the SIP server at the Main Site. According to the Manufacturer the MTU has to be set to 1472 when over IPSec. I tried to set this in the Firewall>Advance>TCP Options
i have tried 1380, 1472, and 1500
none of them have helped at all
I have contacted the ISP and checked to see if there were any issues and confirmed there was not.
I can ping the external IP on all the ASA’s and there is 0 packet loss.
the moment I ping an internal ip at another site is when it occurs.
any help would be much appreciated.
