Hi just wondering if anybody can shed any light on this issue?

I have 2 offices connected via ipsec vpn on subnets Site A on 10.1.1.x to Site B on 11.0.1.x

At each site we have 2 x 2820 routers on the same subnet 1 for Data and 1 for VOIP(Using a Siemens Phone system IP card pointing to this gateway)

Now both routers have separate adsl connections and both have an ipsec vpn tunnel connecting the 10.1.1.x to 11.0.1.x subnets, yet at the 11.0.1.x site the Data router looses all vpn paths (Even though it's tunnels haven't dropped) as soon as the VOIP ipsec tunnel establishes.
It all comes back on as soon as I drop the vpn tunnel on the VOIP router.

This doesn't happen on the 10.1.1.x subnet when the connection establishes.

Any ideas of how I can trace what is happening as this worked fine for 6 months and as soon as the internal cabling was updated at site B this issue started occuring.

I will add that both Data and VOIP routers(At site B) are connected to the same 16 port switch, where before they were in 2 x 8 port switches uplinked.

Thanks

you're evil, why would you do that?