After installing new router with ubuntu 18.04 on it i’m got a problem with working ospf via gre tunnel to my older routers.
All configured simular, but from new router i got ospf state Init/DROther. Older routers (without netplan) dont see any neighbor.
Tunnels work fine with static routing.
I found solution and fix problem manually. I found that netplan make tunnel with ‘ttl inherit’ (on other routers ttl 255).
tunnel1: gre/ip remote 18.104.22.168 local 22.214.171.124 ttl inherit
ip tunnel change tunnel1 ttl 255 command execution ospf starts to work.
How can I add to netplan ttl and pointopoint parameters to tunnel intarface?
How to set commands like below to netplan file?
ifconfig tunnel1 pointopoint 10.2.2.1 ip tunnel change tunnel1 ttl 255
netplan currently lacks the ability to configure the
hoplimit of a tunnel. This issue has been brought up in its issue tracker (bug #1846783), however its developers seem to have not paid attention to this.
Meanwhile you can configure the tunnel using connection managers that support setting this field such as systemd-networkd and NetworkManager, or try to run a script that calls
ip tunnel after the tunnel has been brought up by netplan.