Install on Red Hat Enterprise Linux (RHEL) with multiple IP addresses
RHEL 6 and above are configured by default to apply Strict Reverse Path Forwarding filtering recommended in RFC 3704 – Ingress Filtering for Multihomed Networks.
Due to the default strict filtering, in the cases RHEL has multiple IPs configured and the route for outbound traffic differs from the route of incoming traffic, RHEL may ingnore packets from a remote network.
Environment:
Red Hat Enterprise Linux (RHEL) 6, 7, 8
Required Settings:
If your Brekeke PBX / Brekeke SIP Server has multiple IP addresses and the IP addresses handle incoming packets are different from the one handle outbound packets, the following settings may be required.
By executing the following command, set net.ipv4.conf.all.rp_filter parameter value to 2:
# sysctl net.ipv4.conf.all.rp_filter=2
To make this change persistent, edit /etc/sysctl.conf file and add the following parameter.
net.ipv4.conf.all.rp_filter=2