Creating ipip tunnels in RedHat 8 that is compatible with LVS/TUN.

Every few seasons I built a virtual LVS (Linux Virtual Server) mock up just to keep in shape.  LVS-TUN (lvs/tunnel mode) ipip configuration for RH8 had me stumped for a while.  

There was a change from RH7 to RH8 in that network scripts are being deprecated.  So, /etc/sysconfig/ network scripts behave just a bit different.  For one thing I could not build a reliable ipip tunnel interface in RH8 even after installing and using traditional RH-style network scripts.  

After a lot of difficult tests I am posting the solution for keeping up an ipip tunnel interface for RH8.  Here it is:

# In this example 192.168.131.239 is the RIP (Real Server IP) IP address, 

# 192.168.131.235 is the VIP address.

nmcli con add type ip-tunnel ip-tunnel.mode ipip con-name tun0

          ifname tun0 remote 0.0.0.0 local 192.168.131.239

nmcli con mod tun0 ipv4.addresses 192.168.131.235

nmcli con mod tun0 ipv4.method manual

nmcli con up tun0

The key thing to remember is that the remote ip should be 0.0.0.0.    In RH7 you could use an ipip for LVS-TUN without specifying remote and local IP's.  

If this helps somebody out there with a similar problem, please let me know by replying to this blog.