jwhois [options] query[@server[:port]]
Search a whois database for a domain name, IP address, or NIC name. The information returned varies, but usually contains administrative and technical contacts so that you can find a person to handle problems at that domain. By default, the command
returns information on .com, .net, and .edu domains, but other hosts can be queried for other domains using host or the -h option.
whois linux.com Lookup whois info for hostname or ip add
wget [options] [urls]
Perform noninteractive file downloads from the Web. wget works in the background and can be used to set up and run a download
without the user having to remain logged on. wget supports HTTP, HTTPS, and FTP, as well as downloads through HTTP proxies. wget uses a global startup file that you may find at /etc/wgetrc or /usr/local/etc/wgetrc. In addition, users can define their own $HOME/.wgetrc files.
wget -c http://www.example.com/large.file Continue downloading a partially downloaded file
wget -r -A jpg,jpeg www.xyz.org Download only jpg and jpeg files to the current directory (5 levels deep by default)
wget -r -nd -np -l 1 -A '*.jpg' www.xyz.org Download only jpg files to the current directory (1 level deep)
echo 'wget url' | at 01:00 Download url at 1AM to current dir
wget --limit-rate=20k url Do a low priority download (limit to 20KB/s in this case)
nslookup [-option ... ] [host-to-find | -[server ] ]
TCP/IP command. Query Internet domain nameservers. nslookup is deprecated; its functionality is replaced by the dig and host
commands. nslookup may not be included in some distributions
all List the current settings
This command is often used to perform a reverse lookup on an IP address as shown in the below example.
$ nslookup 188.8.131.52
lftp [options] [url]
File transfer program with more features than ftp. The lftp command allows FTP and HTTP protocol transfers, plus other
protocols including FISH (SSH based), FTPS, and HTTPS. It uses a shell-like command interface and offers job control in a manner
similar to bash. lftp has two important reliability features: it resumes failed or interrupted transactions, and it goes into the
background automatically if it is quit in the middle of a file transfer.
host [options] name [server]
System administration command. Print information about hosts or zones in DNS. Hosts may be IP addresses or hostnames; host
converts IP addresses to hostnames by default and appends the local domain to hosts without a trailing dot. Default servers are
determined in /etc/resolv.conf. For more information about hosts and zones, read Chapters 1 and 2 of Paul Albitz’s and Cricket Liu’s
DNS and BIND
ftp [options] [hostname]
Transfer files to and from remote network site hostname. ftp prompts the user for a command. The commands are listed after
the options. Some of the commands are toggles, meaning they turn on a feature when it is off and vice versa. Note that some versions
may have different options.
-d Enable debugging.
ftp [options] [hostname]