Troubleshooting Linux Network Issues

Troubleshooting Tools

Tool Description Usage Note
ping Test network connectivity ping baidu.com
traceroute Route tracing traceroute ip
route Routing table route -n
netstat Network connections netstat -ano
nslookup DNS resolution nslookup baidu.com
ifconfig Network configuration ifconfig
arp ARP cache arp -a
nbtstat NetBIOS nbtstat -n
netsh Network configuration netsh
net Network configuration net
tcpdump Packet capture tcpdump
wireshark Packet capture wireshark
ip Network configuration ip addr show
ss Network connections ss -tunlp
netstat View network connection state netstat -anp
tcpdump Packet-capture utility tcpdump -i eth0 -nn -s 0 -c 1000 -w /tmp/tcpdump.pcap
iptables Firewall iptables -L -n -v -t nat -t mangle -t filter
ss netstat replacement ss -anp
ifconfig View NIC information ifconfig eth0
ip View NIC information ip addr show eth0
route View routing table route -n
traceroute View routing hops traceroute www.baidu.com
ping Test network connectivity ping www.baidu.com
telnet Test port connectivity telnet www.baidu.com 80
nslookup Domain resolution nslookup www.baidu.com
dig Domain resolution dig www.baidu.com
arp View ARP cache arp -a
netcat Network debugging tool nc -l 1234
nmap Port-scanning tool nmap -sT -p 80 www.baidu.com
mtr Network connectivity tester mtr www.baidu.com
iperf Network performance tester iperf -s -p 1234
iptraf Network traffic monitor iptraf -i eth0
ipcalc IP address calculator ipcalc
iftop Network traffic monitor iftop -i eth0
iostat Disk I/O monitor iostat -x 1 10
vmstat Virtual memory monitor vmstat 1 10
sar System performance monitor sar -n DEV 1 10
lsof Show open file usage lsof -i:80
strace Trace system calls strace -p 1234
tcpflow Packet-capture tool tcpflow -i eth0 -c -C -p -o /tmp/tcpflow
tcpick Packet-capture tool tcpick -i eth0 -C -p -o /tmp/tcpick
tcptrace Packet-capture tool tcptrace -i eth0 -C -p -o /tmp/tcptrace
tcpslice Packet-capture tool tcpslice -i eth0 -C -p -o /tmp/tcpslice
tcpstat Packet-capture tool tcpstat -i eth0 -C -p -o /tmp/tcpstat
tcpdump Packet-capture tool tcpdump -i eth0 -C -p -o /tmp/tcpdump
tshark Packet-capture tool tshark -i eth0 -C -p -o /tmp/tshark
wireshark Packet-capture tool wireshark -i eth0 -C -p -o /tmp/wireshark
socat Network debugging tool socat -d -d TCP-LISTEN:1234,fork TCP:www.baidu.com:80
ncat Network debugging tool ncat -l 1234 -c ’ncat www.baidu.com 80'
netperf Network performance tester netperf -H www.baidu.com -l 60 -t TCP_STREAM
netcat Network debugging tool netcat -l 1234
nc Network debugging tool nc -l 1234
netpipe Network performance tester netpipe -l 1234
netkit Network debugging tool netkit -l 1234
bridge Bridge tool bridge -s