Basic Linux Commands continues from here.
- Netstat – this command means network statistics. This is a very useful tool for network troubleshooting and maintaining performance. We can watch network interface and routing table using this tool. Using this command line tool we can also find what protocol is working on which interface. This can be used for network auditing too.
example: netstat [option]
- Nslookup – this command is a DNS query tool for CLI. It helps search all the data related to a domain name. this is the best tool to resolve domain name system related problems. A nice feature is this can work as both interactive and non interactive mode. We can find different host at a time using this command in interactive mode.
example: nslookup [option] domain name.
- Host – this command is used to convert ip to hostname and hostname into ip. Very easy to use. It requires an argument. If we do not provide any argument to this command than it will show the help page for this command. We often use it for resolving the hostname to ip.
example : host domainname
- Watch – this command is used for observing the real time changes of a command used in CLI. We can provide some number of lines of changes if we want. Also this command shows us all the changes of a command. We have to use another command as argument here. Also we can use interval for watching the changes of the argument.
example: watch date
- Arp – address resolution protocol. This is used to show network neighbor cache. It can also show the members of the routing table and the current content of the network. This tool is mostly used to find the issues of network path if the network is too big or if the system service is required to go through any troubleshoot. This is a very effective tool for finding a big network problem.
example: arp [option] hostname
- Tcpdump – this tool is used for capture packets and analyze. It can be used for watching over a single interface or all the interfaces the system have. It can create file in pcap format and it can analyze by different third party software. One of the most powerful tool on linux platform. Also known as sniffing tool on linux.
example: tcpdump [option] interfacename
- Ss – this is also a network status monitoring tool like netstat. But it has some better features then netstate. Also this is known as new netstat. This tool can show the socket states with different leveling and it can be presented with different manners. There are few useful parameters to represent the network states.
example: ss [option]
- Nmap – network mapper. This command is a very much featured tool on linux platform for network security analysis and auditing. It can scan a very big network and find the hosts on this network with detailed description about that host. Also it can provide the operating system name with its version. So we can say it is a very powerful tool and it can be misused if it goes to a wrong person.
example: nmap –s host-ip/network-ip-range
- Mtr – this tool is also a tool to troubleshoot the routing path like traceroute. But this has added few features with it which makes it better than traceroute. Using this tool we can find the paths that are being used for sending a packet and its hops. One of the very useful feature of this tool is we can save the output as a file.
example: mtr [option] arguments
- Whois – whois a very widely used database worldwide. It keeps a database of different DNS entries and we can find any domain information from here. So this authority created this command line tool to find the authenticity of a domain which also means we can find a lot of information using this tool.
example: whois [option] argumen