Commands by raspi (3)

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Extract busiest times from apache access log
Analyze an Apache access log for the time period with most activity and display the hit count, requesting IP and the timestamp. May help detect a brute force dos attack.

Run a file system check on your next boot.
The empty file /forcefsck causes the file system check fsck to be run next time you boot up, after which it will be removed. This works too: $sudo >/forcefsck

Find all clients connected to HTTP or HTTPS ports
It finds, specifically, the connections to the HTTP and HTTPS ports as source ports. You can check for destination ports as well.

List latest 5 modified files recursively
The output format is given by the -printf parameter: %T@ = modify time in seconds since Jan. 1, 1970, 00:00 GMT, with fractional part. Mandatory, hidden in the end. %TY-%Tm-%Td %TH:%TM:%.2TS = modify time as YYYY-MM-DD HH:MM:SS. Optional. %p = file path Refer to http://linux.die.net/man/1/find for more about -printf formatting. ------------------------ sort -nr = sort numerically and reverse (higher values - most recent timestamp - first) head -n 5 = get only 5 first lines (change 5 to whatever you want) cut -f2- -d" " = trim first field (timestamp, used only for sorting) ------------------------ Very useful for building scripts for detecting malicious files upload and malware injections.

Quick directory bookmarks
Set a bookmark as normal shell variable $ p=/cumbersome/path/to/project To go there $ to p This saves one "$" and is faster to type ;-) The variable is still useful as such: $ vim $p/ will expand the variable (at least in bash) and show a list of files to edit. If setting the bookmarks is too much typing you could add another function $ bm() { eval $1=$(pwd); } then bookmark the current directory with $ bm p

sort a JSON blob
For situations where you keep JSON in a VCS and you want your diffs to be sane, such as within a Chef configuration repo.

Visualizing system performance data

Show Shared Library Mappings
shows which shared lib files are pointed to by the dynamic linker.

Equivalent to ifconfig -a in HPUX
Command is properly working on HP-UX 11.31

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.


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