Commands using ssh (347)

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quickly change all .html extensions on files in folder to .htm

phpinfo from the command line
php -i seems to show default not real

Using a single sudo to run multiple && arguments
This will also work with bash instead of sh shell sudo bash -c 'apt update -y && apt upgrade -y'

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Outputs a 10-digit random number

Expedient hard disk temprature and load cycle stats
This command is a great way to check to see if acpi is doing damage to your disks by agressivly parking the read arm and wearing down it's life. As you can see, mine has lost half its life. I'm sure this could be shortened though somehow. It will use smartctl to dump the stats and then grep out just the temperature and load cycles for the disk (a load cycle is when a the read arm comes out of park and wears on the drive).

Virtualbox: setup hardware
where - memory 256 assign 256 Mb RAM - acpi on enable ACPI (mandatory if you use Winfog 2000 - ioapic off disable the IO APIC. Not useful if you use one CPU (on virtual machine or a 32 bit operative system). As ACPI, this switch is mandatory for Winbug 2000 - pae on enable the Phisical Address Extension how to use more than 4Gb of RAM on x86 CPU - hwvirtex on enables hardware virtualization extensions for microprocessors that have this feature (which should be also enabled in the BIOS of the motherboard) - nestedpaging on allows part of the processes of memory management hardware are made directly

To create files with specific permission:

Run a command for a given time
or "Execute a command with a timeout" Run a command in background, sleep 10 seconds, kill it. $! is the process id of the most recently executed background command. You can test it with: find /& sleep10; kill $!

FAST Search and Replace for Strings in all Files in Directory
I needed a way to search all files in a web directory that contained a certain string, and replace that string with another string. In the example, I am searching for "askapache" and replacing that string with "htaccess". I wanted this to happen as a cron job, and it was important that this happened as fast as possible while at the same time not hogging the CPU since the machine is a server. So this script uses the nice command to run the sh shell with the command, which makes the whole thing run with priority 19, meaning it won't hog CPU processing. And the -P5 option to the xargs command means it will run 5 separate grep and sed processes simultaneously, so this is much much faster than running a single grep or sed. You may want to do -P0 which is unlimited if you aren't worried about too many processes or if you don't have to deal with process killers in the bg. Also, the -m1 command to grep means stop grepping this file for matches after the first match, which also saves time.


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