This is a static archive of our old Q&A Site. Please post any new questions and answers at ask.wireshark.org.

TCP package loss? via VPN connection

0

I am testing connecting a outside computer via vpn to my network and log in a softphone software. The connection is made through port 1500 on the server (172.24.7.12).

When you do the vpn connection the router gives you a fixed internal ip (configurable on the router).

Weird problem when i log into the vpn with the ip 172.24.4.2 (and only this ip) the host packets get lost somewhere in the network , i see in wireshark that it doesn't receive all the ACK and etc necessary for the connection. Sometimes it doesn't receive anything at all even though i can ping with no problem (i see the ICMP in wireshark) but it doesn't show anything in port 1500. And other times it just connects OK with no problems it seems completely random..

This only happens when i use this specific ip if i use per example 172.24.4.3 all works fine.

Anyone has any ideia what it might be? If you need i can try to collect and share the wireshark entries of several tries.

If it's to complicated it's ok i've already busted my head trying to figuring this out i think i'm just going to ignore this problem and never use that IP :,D

EDIT: btw i've checked every place the packets go through and they should get the same "treatement" if they come from 172.24.4.2 or 172.24.4.3

asked 19 Nov '15, 06:21

mike3645's gravatar image

mike3645
1112
accept rate: 0%

edited 19 Nov '15, 06:23


One Answer:

0

Weird problem when i log into the vpn with the ip 172.24.4.2
This only happens when i use this specific ip if i use per example 172.24.4.3 all works fine.

Sounds like there is a route on either your VPN gateway or on the internal system for 172.24.4.2, or either one of these two (internal system or VPN gateway) has this IP address configured as secondary or on a second interface. Did you check that?

Regards
Kurt

answered 19 Nov '15, 09:32

Kurt%20Knochner's gravatar image

Kurt Knochner ♦
24.8k1039237
accept rate: 15%