Can't get LAN to work

Issues related to configuring your network
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wp.rauchholz
Posts: 133
Joined: 2016/11/20 11:58:45

Can't get LAN to work

Post by wp.rauchholz » 2021/01/12 12:53:42

I am trying to setup my Centos 8 box as a modem/router. I had it running under Centos 7, no prob.
I am using good old iptables becasue I fell more comfortable with. firewalld is disabled. I plan to move to nftables later.
I configured enp3s0 (LAN) as static
enp5s0 has BOOTPROTO 0f none.
I setup pppoe using pppoe-setup (I found a rp-pppoe for el8)

The interfaces are up and running. I can connect with my laptop to enp3s0.
DHCP and DNS are up and running. Selinux is disabled.
/proc/sys/net/ipv4/ip_forward is set to 1
I can startup ppp0 and connect to my ISP (I can dig redhat.com, etc..), but I do not get internet through to the LAN.
I am rtying to debug. The only thing I can find is this:

Jan 12 13:33:44 home.wo-lar.com NetworkManager[1067]: <info> [1610454824.8855] device (ppp0): state change: disconnected -> unmanaged (reason 'unmanaged', sys-iface-state: 'external')
Jan 12 13:33:45 home.wo-lar.com NetworkManager[2022]: <info> [1610454825.2591] manager: (ppp0): new Ppp device (/org/freedesktop/NetworkManager/Devices/4)
Jan 12 13:33:45 home.wo-lar.com NetworkManager[2022]: <inf o> [1610454825.2596] device (ppp0): state change: unmanaged -> unavailable (reason 'managed', sys-iface-state: 'external')
Jan 12 13:33:45 home.wo-lar.com NetworkManager[2022]: <info> [1610454825.2643] device (ppp0): state change: unavailable -> disconnected (reason 'none', sys-iface-state: 'managed')


And a follow-up question:
I had planned to disable NetworkManager and set the ONBOOT=yes. But this appears not to work. Is the NetworkManager absolutetly required to bring the interfaces up?




Thanks for your help.

tunk
Posts: 900
Joined: 2017/02/22 15:08:17

Re: Can't get LAN to work

Post by tunk » 2021/01/12 16:36:15

On a C8 box I've disabled NetworkManager, IIRC following this:
https://www.thegeekdiary.com/how-to-dis ... os-rhel-8/

wp.rauchholz
Posts: 133
Joined: 2016/11/20 11:58:45

Re: Can't get LAN to work

Post by wp.rauchholz » 2021/01/12 19:27:58

Hi tunk,

thanks for the help. I think I will do the same.
I tried to get it work with NetworkManager and I believe I know now why it is not working; NetworkManager does not look in /etc/sysconfig/network-scripts for the ppp0 config but in /etc/NetworkManager.

Wolfgang

wp.rauchholz
Posts: 133
Joined: 2016/11/20 11:58:45

Re: Can't get LAN to work

Post by wp.rauchholz » 2021/01/12 19:41:48

I might have found something...
https://gitlab.freedesktop.org/snippets/638

wp.rauchholz
Posts: 133
Joined: 2016/11/20 11:58:45

Re: Can't get LAN to work

Post by wp.rauchholz » 2021/01/16 13:10:31

I gave up on trying to use NetworkManager to setup my box as modem/router. I went back to network-scripts as thos worked under Centos 7.
But here too, I ran into an issue I cannot solve and google does not help. Maybe I find a soluton here:
I stopped/disbabled and removed NetworkManager. I installed network-scripts and rp-pppoe
I configured the NICs and ran pppoe-setup. But noe I get he error mesage:
/etc/sysconfig/network-scripts/ifup-eth[3759]: Device pp0 does not seem to be present, delaying initialization.

Tw proposed fix is to empty /etc/udev/rules.d/70-persistent-net.rules. THis file does not even exist. So I added it by using touch and rebooted.
But still no fix. Any idea what I am doing wrong?

Thanks

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