Solved CentOS 7 enabling Telnet
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@dbeato said in CentOS 7 enabling Telnet:
@dustinb3403 said in CentOS 7 enabling Telnet:
I just figured it out, it's using the default port. 23 rather than the port I thought I added correctly.
What if you create an IPTable forwarding from that 9090 port to the internal port 23? Does that work?
How would I do that?
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@dustinb3403 said in CentOS 7 enabling Telnet:
@dbeato said in CentOS 7 enabling Telnet:
@dustinb3403 said in CentOS 7 enabling Telnet:
I just figured it out, it's using the default port. 23 rather than the port I thought I added correctly.
What if you create an IPTable forwarding from that 9090 port to the internal port 23? Does that work?
How would I do that?
Actually, something along this lines might be good:
http://sharadchhetri.com/2014/12/08/change-telnet-server-port-number-centos-7-rhel-7/ -
@dbeato I'm already reading it, but systemd fails to restart the service with
systemctl status telnet.socket ā telnet.socket - Telnet Server Activation Socket Loaded: loaded (/usr/lib/systemd/system/telnet.socket; enabled; vendor preset: disabled) Active: failed (Result: resources) since Thu 2018-06-07 08:35:37 EDT; 14min ago Docs: man:telnetd(8) Listen: [::]:9090 (Stream) Accepted: 1; Connected: 0 Jun 07 08:37:31 server systemd[1]: Starting Telnet Server Activation Socket. Jun 07 08:37:51 server systemd[1]: telnet.socket failed to listen on sockets: Permission denied Jun 07 08:37:51 server systemd[1]: Failed to listen on Telnet Server Activation Socket. Jun 07 08:37:51 server systemd[1]: Starting Telnet Server Activation Socket. Jun 07 08:40:15 server systemd[1]: telnet.socket failed to listen on sockets: Permission denied Jun 07 08:40:15 server systemd[1]: Failed to listen on Telnet Server Activation Socket. Jun 07 08:40:15 server systemd[1]: Starting Telnet Server Activation Socket. Jun 07 08:49:31 server systemd[1]: telnet.socket failed to listen on sockets: Permission denied Jun 07 08:49:31 server systemd[1]: Failed to listen on Telnet Server Activation Socket. Jun 07 08:49:31 server systemd[1]: Starting Telnet Server Activation Socket.
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@dustinb3403 said in CentOS 7 enabling Telnet:
@dbeato said in CentOS 7 enabling Telnet:
@dustinb3403 said in CentOS 7 enabling Telnet:
I just figured it out, it's using the default port. 23 rather than the port I thought I added correctly.
What if you create an IPTable forwarding from that 9090 port to the internal port 23? Does that work?
How would I do that?
For the firewall rules this is what I would use:
firewall-cmd --zone=public --add-port=9009/tcp --permanent firewall-cmd --reload semanage port -a -t telnetd_port_t -p tcp 9099
Also are you modifying the following file?
/usr/lib/systemd/system/telnet.socket
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and the journalctl logs has
-- Unit telnet.socket has begun starting up. Jun 07 08:50:48 server polkitd[713]: Unregistered Authentication Agent for unix-process:3613:205717 (system bus name :1.48, object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_US. Jun 07 08:57:21 server firewalld[743]: WARNING: ALREADY_ENABLED: 9090:tcp Jun 07 08:58:16 server polkitd[713]: Registered Authentication Agent for unix-process:3803:250497 (system bus name :1.53 [/usr/bin/pkttyagent --notify-fd 5 --fallback], object path /org/freedesktop/ Jun 07 08:58:16 server polkitd[713]: Unregistered Authentication Agent for unix-process:3803:250497 (system bus name :1.53, object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_US. Jun 07 08:59:03 server polkitd[713]: Registered Authentication Agent for unix-process:3820:255214 (system bus name :1.54 [/usr/bin/pkttyagent --notify-fd 5 --fallback], object path /org/freedesktop/ Jun 07 08:59:03 server systemd[1]: Reloading. Jun 07 08:59:04 server polkitd[713]: Unregistered Authentication Agent for unix-process:3820:255214 (system bus name :1.54, object path /org/freedesktop/PolicyKit1/AuthenticationAgent, locale en_US. Jun 07 08:59:11 server polkitd[713]: Registered Authentication Agent for unix-process:3840:255990 (system bus name :1.55 [/usr/bin/pkttyagent --notify-fd 5 --fallback], object path /org/freedesktop/ Jun 07 08:59:11 server systemd[1]: telnet.socket failed to listen on sockets: Permission denied Jun 07 08:59:11 server systemd[1]: Failed to listen on Telnet Server Activation Socket.
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@dbeato said in CentOS 7 enabling Telnet:
@dustinb3403 said in CentOS 7 enabling Telnet:
@dbeato said in CentOS 7 enabling Telnet:
@dustinb3403 said in CentOS 7 enabling Telnet:
I just figured it out, it's using the default port. 23 rather than the port I thought I added correctly.
What if you create an IPTable forwarding from that 9090 port to the internal port 23? Does that work?
How would I do that?
For the firewall rules this is what I would use:
firewall-cmd --zone=public --add-port=9009/tcp --permanent firewall-cmd --reload semanage port -a -t telnetd_port_t -p tcp 9099
Also are you modifying the following file?
/usr/lib/systemd/system/telnet.socket
Yes I've done all of this.
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@dustinb3403 said in CentOS 7 enabling Telnet:
@dbeato said in CentOS 7 enabling Telnet:
@dustinb3403 said in CentOS 7 enabling Telnet:
@dbeato said in CentOS 7 enabling Telnet:
@dustinb3403 said in CentOS 7 enabling Telnet:
I just figured it out, it's using the default port. 23 rather than the port I thought I added correctly.
What if you create an IPTable forwarding from that 9090 port to the internal port 23? Does that work?
How would I do that?
For the firewall rules this is what I would use:
firewall-cmd --zone=public --add-port=9009/tcp --permanent firewall-cmd --reload semanage port -a -t telnetd_port_t -p tcp 9099
Also are you modifying the following file?
/usr/lib/systemd/system/telnet.socket
Yes I've done all of this.
Interesting, I am not sure then.
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@dbeato I've even modified the predefined service at /usr/lib/firewalld/services/telnet.xml to use port 9090 and the service still fails to load.
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And I got the port forwarding to work.
firewall-cmd --zone=public --add-forward-port=port=9090:proto=tcp:toport=23
I can now telnet to my server on port 9090 (which forward to 23).
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@dustinb3403 said in CentOS 7 enabling Telnet:
And I got the port forwarding to work.
firewall-cmd --zone=public --add-forward-port=port=9090:proto=tcp:toport=23
I can now telnet to my server on port 9090 (which forward to 23).
Nice!