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May be you have crossed IP's at tunnels?
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Actually, that problem was resolved by creating static routes for each of the tunnels. Strangely, I have only one WAN interface, but the Cisco IOS couldn't route the tunnels using single routing default route from NAT to WAN.
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Actually, that problem was resolved by creating static routes for each of the tunnels. Strangely, I have only one WAN interface, but the Cisco IOS couldn't route the tunnels using single routing default route from NAT to WAN.

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Hi, I have a dilema with configuring IPSec site-to-site vpn. I have five office loations and I can configure three tunnels on each router without any hitch. However, when I try to configure the fourth or fifth tunnel, a pop-up message shows to disable an existing tunnel to enable the fourth one. <br />
<br />
At first, I thought this was due to some licensing issue. However, after checking with the Cisco reseller, they told me I can do up to 200 site to site IPSecs. I have three Cisco 2811's, one 2851 , and another 3845, all with base VPN modules.<br />
<br />
I am lost... what should I do next?<br />
<br />
Thank you.
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Hi, I have a dilema with configuring IPSec site-to-site vpn. I have five office loations and I can configure three tunnels on each router without any hitch. However, when I try to configure the fourth or fifth tunnel, a pop-up message shows to disable an existing tunnel to enable the fourth one. 

At first, I thought this was due to some licensing issue. However, after checking with the Cisco reseller, they told me I can do up to 200 site to site IPSecs. I have three Cisco 2811's, one 2851 , and another 3845, all with base VPN modules.

I am lost... what should I do next?

Thank you.

Cisco 2851 IPSec VPN tunnels issue

A virtual private network (VPN) is a network that uses a public telecommunication infrastructure, such as the Internet, to provide remote offices or travelling users access to a central organizational network securely. VPNs encapsulate data transfers using secure cryptographic methods and other security mechanisms to ensure that only authorized users can access the network and that the data cannot be intercepted.

A router is a networking device that forwards data packets between computer networks. Routers perform the "traffic directing" functions on the Internet. The most familiar type of routers are home and small office cable or DSL routers that simply pass data, such as web pages, email, IM, and videos between computers and the Internet. More sophisticated routers, such as enterprise routers, connect large business or ISP networks up to the powerful core routers that forward data at high speed along the optical fiber lines of the Internet backbone. Though routers are typically dedicated hardware devices, use of software-based routers has grown increasingly common.

Routers

Internet Protocol Security (IPsec) is a protocol suite for secure Internet Protocol (IP) communications by authenticating and encrypting each IP packet of a communication session. IPsec includes protocols for establishing mutual authentication between agents at the beginning of the session and negotiation of cryptographic keys to be used during the session. IPsec can be used in protecting data flows between a pair of hosts (host-to-host), between a pair of security gateways (network-to-network), or between a security gateway and a host (network-to-host). IPsec is an end-to-end security scheme operating in the Internet Layer of the Internet Protocol Suite.