After administering Unix or Unix-like servers, what tools (command-line preferably) do you feel you cannot live without?
The shutdown command.
All the standard commands and utilities (Bash, grep, sed, AWK, find, xargs, ssh, Vim, etc.)
- Lsof, awesome in so many ways, I love to use it for finding open ports AND the files associated with that process.
- Screen, for multi-session awesome.
- Tcpdump, its funny how many application problems are really weird network issues
- Ruby, makes more sense to me than Perl, becoming wildly popular for SA work.
- Chef, configuration management system.
- Capistrano, ssh in a for loop, but less crappy. And in Ruby.
- Rake, more sensible than make.
- rsync running over ssh to keep things consistent... in multiple directions (-gloptru[n]c)
- Vim and vimdiff to edit with 'folding' and viewing differences in scripts, logs, etc.
- Perl and (Ba)sh for scripting and analysis
- cURL (and maybe Wget) for posting/fetching data from ...
- Apache to webify them all (or at least create point-n-click admin tools)
Haven't seen anyone mention this yet.
The nmon tool is designed for AIX and Linux performance specialists to use for monitoring and analyzing performance data, including:
- CPU utilization
- Memory use
- Kernel statistics and run queue information
- Disks I/O rates, transfers, and read/write ratios
- Free space on file systems
- Disk adapters
- Network I/O rates, transfers, and read/write ratios
- Paging space and paging rates
- CPU and AIX specification
- Top processors
- and more
Can be run in file mode which generates a big CSV file. IBM also provide an Excel macro for parsing this and turning it in to awesome graphs, although you do need a Windows VM for that.