We recently acquired a redundant wireless modem at the office, I quickly realized that it would cause issues with several programs already established since it took over DHCP and changed our subnet. So I set up Named & DHCPD to maintain the subnet as it was and everything has been running smoothly so far. What I’m having problems doing is setting up our intranet (eno1) to be forwarded to the redundancy modem (eno2). I had successfully set it up shortly after the modem was set up, but realized the changes were runtime & lost when I updated & rebooted the server.
Granted that wasn’t entirely bad, because when forwarding we lost access to the VPN even though the redundant modem is connected to the primary & as long as internet is available, all traffic goes through our ISP modem. The ISP has the redundant modem locked down so I am unable to perform any port forwarding to bypass this.
What I’m trying to do is determine the exact commands needed to re-establish the forwarding between eno1 & eno2. So that I can’t write a script that will automatically forward traffic when our landline isp connection drops. I was using IPTables when I first got it set up, but have been unsuccessful at replicating it since the restart. I have attempted to use FirewallD direct rules to set up postrouting w/ masquerade & forwarding with no luck. And I have also resorted to going back to IPTables but have also had no luck.
After numerous google searches I have become desperate & now ask for help.
Before it’s said, yes ipforwarding is on in sysctl. I currently have both interfaces in the same zone. My latest attempt consisted of the following commands:
firewall-cmd --direct --add-rule ipv4 nat POSTROUTING 0 -o eno2 -j MASQUERADE
firewall-cmd --direct --add-rule ipv4 filter FORWARD 0 -i eno1 -o emo2 -j ACCEPT
firewall-cmd --direct --add-rule ipv4 filter FORWARD 0 -i eno2 -o eno1 -m state --state RELATED,ESTABLISHED -j ACCEPT
Both runtime and permeant were used with no success. Any advice or guidance would be greatly appreciated.