Cisco Simple GRE with IPSEC Tunnels
GRE with IPSEC KB ID 0000951 Problem I’ve spent years setting up VPN tunnels between firewalls. The only time I’ve ever dealt with GRE is for letting VPN client software though firewalls. GRE’s job is to ‘encapsulate’ other protocols and transport those protocols inside a virtual point to point link. Below is the topology, I’m going to use. The tunnel will run form Router R1 to Router R3, once...
Cisco – Configuring Dynamic Multipoint Virtual Private Networks DMVPN
DMVPN KB ID 0000954 Problem A while back I uploaded a run through on how to deploy GRE tunnels and protect those tunnels with IPsec. That point-to-point GRE tunnel is a good solution, but if you have a lot of sites it’s not a solution that scales very well. Yes you can have 2147483647 tunnel interfaces, but good luck manually configuring all those tunnels and even if you did, if you want each of your remote sites to talk to each...
Windows SSH ‘No Matching Key’
No Matching Key KB ID 0001900 Problem : No Matching Key Typically I see this problem on my mac or within various Linux distributions. I’ve covered extensively how to fix this on a mac in the following article. macOS – SSH Error ‘No Matching Exchange Method Found’ So when I saw the same question asked for a Windows client, I went and looked, and found some patchy information, so I thought I’d work it out and post it here...
Cisco ASA to Fortigate VPN (Properly!)
KB ID 0001721 Problem A while ago I did a run through on site to site VPNs from Cisco ASA to Fortigate firewalls. Back then I said that the default settings were a bit ‘shoddy’ and that I’d revisit it once I had more time. What do you mean shoddy? Well, Cisco and Fortinet are both guilty of enabling ‘Everything’ to make the tunnel come up, so people can just use a wizard and not put to much thought into...
VMware Edge Gateway VPN to Cisco ASA
KB ID 0001658 Problem I was asked to setup a VPN to help out a colleague this week. When I had a look, one end turned out to be an Edge Gateway, I wasn’t that concerned, I’d done similar things in my prior role, I just didn’t have access to the vCloud or VMware at this datacenter. Depite my best efforts on the ASA, the tunnel refused to come up, it took a little looking ‘under the covers’ to accurately...