Commands by IndustrialJoe (1)

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Test file system performance
You need bonnie++ package for this. More detail than a simple hdparm -t /dev/sda would give you. the -d is the directory where it performs writes/reads for example I use /tmp/scratch with 777 permissions Bonnie++ benchmarks three things: data read and write speed, number of seeks that can be performed per second, and number of file metadata operations that can be performed per second.

Don't spam root. Log your cronjob output to syslog
This command will log the output of your simple cronjobs to syslog, and syslog will take it from there. Works great for monitoring scripts which only produce simple output. Advantages: * This can be used by regular users, without modifying system files like /etc/syslog.conf * Reduce cron spam to [email protected] (Please stop spaming the sysadmins) * Uses common tools like syslog (and logrotate) so that you don't need to maintain yet another krufty logfile. * Still ensures that the output is logged somewhere, for posterity. Perhaps it's stored the secure, central syslog server, for example. * Seems to work fine on Ubuntu, CentOS, FreeBSD & MacOSX

Use find to get around Argument list too long problem
Can be used for other commands as well, replace rm with ls. It is easy to make this shorter but if the filenames involved have spaces, you will need to do use find's "-print0" option in conjunction with xargs's "-0" option. Otherwise the shell that xargs uses to execute the "rm" command line will treat the space as a token separator, thereby treating the name as two (or more) names.

Rescan partitions on a SCSI device
Used this after cloning a disk with dd to make the newly written partitions show up in /dev/

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

Insert a comment on command line for reminder
Comments can be used directly on the command line so I can save in the history a brief description of what command does.

Add date stamp to filenames of photos by Sony Xperia camera app
Sony's Xperia camera app creates files without time-stamped names. Thus, after deleting files on the phone, the same names will be reused. When uploading the photos to a cloud storage, this means that files will be overwritten. Running this command after every sync of uploaded photos with the computer prevents this.

find duplicate processes
This command will allow to search for duplicate processes and sort them by their run count. Note that if there are same processes run by different users you'll see only one user in the result line, so you'll need to do: $ ps aux | grep to see all users that run this command.

recursive base64 encoding -- Cipher for the Poor ?
Just for fun, I searched a simple way to encrypt some text. Simple base64 encoding seemed a good start so I decided to "amplify" encoding using repeted base64 encoding. Of course, this is not really secure but can be useful to hide datas to most part of humans ;). Do not hesitate to provide better solutions or else.


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