i have tried monitoring packets, but the amount of information is defeating me, in a previous version of centos i could use bandwidth monitoring to summarize the traffic for a period by port, but i have not found how to do this for the current server
i have tried to drop all out going packets on port 53, using firewalld form information found on various websites, but so far have been unsuccessful
so obviously i am doing it wrong somehow, i have also tried using the firewall-config applicaton, and not even sure if port 53 is the main culprit, but it did solve a problem for me with the previous server> systemctl status firewalld
● firewalld.service - firewalld - dynamic firewall daemon
Loaded: loaded (/usr/lib/systemd/system/firewalld.service; enabled; vendor preset: enabled)
Active: active (running) since Mon 2018-05-28 07:12:37 AEST; 3 days ago
Docs: man:firewalld(1)
Main PID: 19913 (firewalld)
CGroup: /system.slice/firewalld.service
└─19913 /usr/bin/python -Es /usr/sbin/firewalld --nofork --nopid
May 29 21:51:19 localhost.localdomain firewalld[19913]: ERROR: COMMAND_FAILED
May 29 21:51:32 localhost.localdomain firewalld[19913]: WARNING: '/usr/sbin/iptables-restore --wait=2 -n' failed: iptables-restore v1.4.21: Couldn't load match `--sport=53':No such file or directory
Error occurred at line: 2
Try `iptables-restore -h' or 'iptables-restore --help' for more information.
May 29 21:51:32 localhost.localdomain firewalld[19913]: ERROR: COMMAND_FAILED
May 29 21:51:51 localhost.localdomain firewalld[19913]: WARNING: '/usr/sbin/iptables-restore --wait=2 -n' failed: iptables-restore v1.4.21: Couldn't load match `--sport=53':No such file or directory
Error occurred at line: 2
Try `iptables-restore -h' or 'iptables-restore --help' for more information.
May 29 21:51:51 localhost.localdomain firewalld[19913]: ERROR: COMMAND_FAILED
May 29 21:52:21 localhost.localdomain firewalld[19913]: WARNING: '/usr/sbin/iptables-restore --wait=2 -n' failed: iptables-restore v1.4.21: Couldn't load match `--sport=53':No such file or directory
Error occurred at line: 2
Try `iptables-restore -h' or 'iptables-restore --help' for more information.
May 29 21:52:21 localhost.localdomain firewalld[19913]: ERROR: COMMAND_FAILED
May 29 21:54:24 localhost.localdomain firewalld[19913]: WARNING: '/usr/sbin/iptables-restore --wait=2 -n' failed: iptables-restore v1.4.21: Couldn't load match `--sport=53':No such file or directory
Error occurred at line: 2
Try `iptables-restore -h' or 'iptables-restore --help' for more information.
May 29 21:54:24 localhost.localdomain firewalld[19913]: ERROR: COMMAND_FAILED
May 29 22:28:43 localhost.localdomain firewalld[19913]: ERROR: Failed to load direct rules file '/etc/firewalld/direct.xml': INVALID_TYPE: Not a valid file: no element found: line 2, column 0
what information do i need to post to help?