Appends output to the file, some systems require the -a to do this.

Very similar as doing "wget http://example.com/mytarball|tar xzv", this one involves the "tee" command between both, which will simultaneously write the tarball and copy it to stdout. So this command will locally save the tarball and extract it - both at the same time while it downloads.

Replace the first part of the command above with the appropriate timezone string. Eg: 'Europe/London' or for UTC - 'Etc/UTC'. The appropriate string can be found from https://en.wikipedia.org/wiki/List_of_tz_database_time_zones This is useful when your server is installed by a data centre (managed hardware, VPS, etc) and the timezone is not usually set to the one your prefer.

Pipes the header row of ps to STDERR, then greps for the command on the output of ps, removing the grep entry before that. Show Sample Output

This is to overcome the issue of slow I/O by reading once and forwarding the output to several processes (e. g. 3 in the given command). One could also invoke grep or other programs to work on read data. Show Sample Output

Many circumstances call for creating variable of a summary result while still printing the original pipe. Inserting "tee >(cat >&2)" allows the command output to still be printed while permitting the same output to be processed into a variable. Show Sample Output

This will write to TAPE (LTO3-4 in my case) a backup of files/folders. Could be changed to write to DVD/Blueray. Go to the directory where you want to write the output files : cd /bklogs Enter a name in bkname="Backup1", enter folders/files in tobk="/home /var/www". It will create a tar and write it to the tape drive on /dev/nst0. In the process, it will 1) generate a sha512 sum of the tar to $bkname.sha512; so you can validate that your data is intact 2) generate a filelist of the content of the tar with filesize to $bkname.lst 3) buffer the tar file to prevent shoe-shining the tape (I use 4GB for lto3(80mb/sec), 8gb for lto4 (120mb/sec), 3Tb usb3 disks support those speed, else I use 3x2tb raidz. 4) show buffer in/out speed and used space in the buffer 5) show progress bar with time approximation using pv ADD : To eject the tape : ; sleep 75; mt-st -f /dev/nst0 rewoffl TODO: 1) When using old tapes, if the buffer is full and the drive slows down, it means the tape is old and would need to be replaced instead of wiping it and recycling it for an other backup. Logging where and when it slows down could provide good information on the wear of the tape. I don't know how to get that information from the mbuffer output and to trigger a "This tape slowed down X times at Y1gb, Y2gb, Y3gb down to Zmb/s for a total of 30sec. It would be wise to replace this tape next time you want to write to it." 2) Fix filesize approximation 3) Save all the output to $bkname.log with progress update being new lines. (any one have an idea?) 4) Support spanning on multiple tape. 5) Replace tar format with something else (dar?); looking at xar right now (https://code.google.com/p/xar/), xml metadata could contain per file checksum, compression algorithm (bzip2, xv, gzip), gnupg encryption, thumbnail, videopreview, image EXIF... But that's an other project. TIP: 1) You can specify the width of the progressbar of pv. If its longer than the terminal, line refresh will be written to new lines. That way you can see if there was speed slowdown during writing. 2) Remove the v in tar argument cvf to prevent listing all files added to the archive. 3) You can get tarsum (http://www.guyrutenberg.com/2009/04/29/tarsum-02-a-read-only-version-of-tarsum/) and add >(tarsum --checksum sha256 > $bkname_list.sha256) after the tee to generate checksums of individual files !

get master info: head -n 40 /home/db_bak.sql |awk '$0~/MASTER_LOG_FILE/ slave server: change master ??. start slave

This command allows to follow up a trace on SDP (CS5.2), at the same time as the trace records are stored in the file with "raw" format. Trace files in native format are useful to filter the records before to translation from '|' to '\n'. Example: grep -v OP_GET <raw-records>.trace | tr '|' '\n' Show Sample Output

Use tee -a to append.

Create a file with random binary content. Required pv, units packages. It use openssl to encrypt zeros using aes-256 and time stamp as password to generate a pseudo-random file. Show Sample Output

This might one day deliver the melody to the next super hit on the radio if played long enough

Use comm command to compare two text files and display lines that are exactly the same on both files and write those to a new output file using tee

Stat -c %n #list files. A find command is also useful Tee #use stdout, but reseend to next comand. Can be other Tee ad infinitum xargs #use de name of files to execute md5 and sha diggest.

List all your public IPs in an EC2/AWS region, and run an nmap scan against them (ignoring ping response). Requires: aws cli, jq for shell JSON processing Show Sample Output

netstat doesn't always function similarly across the board. Also the use of three commands in the original (netstat followed by grep followed by grep) is a waste of pipes