# The Strict mode of RFC3704 Reverse Path filtering breaks some pretty # common and reasonable use cases. # # Notably, it makes it impossible for NetworkManager to do connectivity # check on a newly arriving default route (it starts with a higher metric # and is bumped lower if there's connectivity). # # Kernel's default is 0 (no filter), systemd configures a Loose filter since # commit 230450d4e4f1 ('sysctl.d: switch net.ipv4.conf.all.rp_filter from 1 # to 2'). However, RHEL systemd package happens to default to Strict mode # for historic reasons. Let's override it if we're doing connectivity # checking. # Source route verification net.ipv4.conf.all.rp_filter = 0