How to create NetworkManager dispatcher script to remove local route?

Solution Verified - Updated -

Environment

  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat Enterprise Linux 10
  • NetworkManager

Issue

  • How to create NetworkManager dispatcher script to remove local route?
  • How to remove local route persistently?

Resolution

NOTE: Removing a local route can break Layer 2 (L2) communication on the server. Before applying this solution, ensure it will not cause any unintended impact.

  • Create a file named 99-remove-route inside the /etc/NetworkManager/dispatcher.d/ directory with the following content:
#!/bin/bash
if [ "$2" = "up" ]; then
    /usr/sbin/ip route del  192.0.2.0/24<-Specify the local Network
fi
  • Grant execute permission to the script and Restart the NetworkManager service to apply the changes.
$ chmod a+x /etc/NetworkManager/dispatcher.d/99-remove-route
$ systemctl restart NetworkManager

Diagnostic Steps

  • Check the route by executing following command

Before:

$ ip route show all 
default via 192.0.2.1 dev ens2 proto static metric 100 
192.0.2.0/24 dev ens2 proto kernel scope link src 192.0.2.2 metric 100

After:

$ ip route show all 
default via 192.0.2.1 dev ens2 proto static metric 100

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