When your Linux server seems to have network issues, you should be able to log in via VNC console to troubleshoot the issue
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ip addr show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
link/ether f2:3c:93:60:50:30 brd ff:ff:ff:ff:ff:ff
inet 178.00.000.000/24 brd 178.00.000.255 scope global eth0
valid_lft forever preferred_lft forever
inet6 2a01:7e00::f03c::5030/64 scope global dynamic mngtmpaddr noprefixroute
valid_lft 5155sec preferred_lft 1555sec
inet6 fe80::f03c::5030/64 scope link
valid_lft forever preferred_lft forever |
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| language | bash |
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ifconfig #only displays enabled interfaces. |
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| language | bash |
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ping google.com
PING google.com (200.0.000.000) 56(84) bytes of data.
64 bytes from par.net (200.0.000.000): icmp_seq=1 ttl=117 time=21.4 ms
64 bytes from par.net (200.0.000.000): icmp_seq=2 ttl=117 time=23.6 ms
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mtr google.com
My traceroute [v0.92]
hostname (0.0.0.0) Thu Jun 21 12:00:00 2024
Keys: Help Display mode Restart statistics Order of fields quit
Packets Pings
Host Loss% Snt Last Avg Best Wrst StDev
1. router1 0.0% 5 1.0 1.2 0.9 1.5 0.2
2. isp-router 0.0% 5 9.1 10.2 8.3 12.5 1.2
3. destination-router 0.0% 5 20.5 15.9 14.3 20.5 2.0
4. google.com 0.0% 5 21.7 18.3 17.1 21.7 1.8 |
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netstat # Display all the active network connections, routing tables, and interface statistics on your Linux system.
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This helps in understanding what applications or daemons are running and potentially causing issues, crucial for troubleshooting port conflicts or unauthorized services running on unexpected ports. Useful in verifying firewall rules and monitoring for unauthorized services or suspicious network activity |
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netstat -tulpn #shows all programs listening for connections, along with their details like ports and IDs, using numbers instead of names.
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 127.0.0.53:53 0.0.0.0:* LISTEN -
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN -
tcp 0 0 127.0.0.1:46565 0.0.0.0:* LISTEN 1616/eidLvUIServer
tcp6 0 0 :::45623 :::* LISTEN 71127/AppRun.wrappe
tcp6 0 0 :::5061 :::* LISTEN 71127/AppRun.wrappe
tcp6 0 0 ::1:631 :::* LISTEN -
tcp6 0 0 :::1716 :::* LISTEN 1614/kdeconnectd
udp 0 0 0.0.0.0:52881 0.0.0.0:* - |
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