Linux admin shortcuts

List of sometimes useful commands

System information

Getting hardware information

Hardware information can be obtained using the dmidecode tool that tries to decode the dmi table. It can also filter the information provided using the -t flag.
Getting information the physical memory:

dmidecode -t memory

 

Getting information about a domain

Domain information cat be obtained using the DNS lookup utility dig. The simplest usage would be:

dig domainname

and it returns information on the A record of the host.
The utility can be used to get other types of information by using the -t switch and specifying the record type. For nameservers the query is:

dig domainname -t NS

For mail records:

dig domainname -t MX

Reverse lookups can be prformed using the -x flag:

dig -x ip_address