Get the size of the folders in any directory
du -sh folder_location/*
Get the size of folders in the current directory
sudo du -chax --max-depth=1 . | grep -E "M|G"
Search for content of a file from the command line
grep [--include=file_pattern.extension] -rnwl "matching pattern"
Create a new SVN Repo
sudo svnadmin create /svn/repos/repo_name
sudo chown -R www-data:www-data /svn/repos/repo_name
Remove Directory and Contents
rm -r mydir
List CPU Usage of running processes
Get Wireless Signal Information
will save in /tmp/file_list_$FOLDER an alphabetically ordered list of all the files inside $FOLDER, complete with the corresponding sub-folders
find $FOLDER -type f | cut -d/ -f2- | sort > /tmp/file_list_$FOLDER
Display all processes accessing a folder or drive (source)
sudo fuser -mv /folder
zpool change mount location (source)
zfs set mountpoint=/myspecialfolder mypool
When migrating servers it’s best to leave a few months overlap on your old hosting contract. It’s a pain to pay double for a while but it’s critical to preventing downtime.
The first thing to do is get all your files moved over to the new server and test to make sure everything is working the same. Once you are satisfied that your new server is operating properly you can do a “full test run” with the DNS server configurations.
On your old hosting remove the DNS A Records for your old hosting server. It will typically be in there by default. Add a new custom DNS A record pointing to your new server.
This effectively redirects all traffic from your old hosting to the copy on the new hosting. Sometimes it takes as much as 48 hours for these changes to go into effect but in my experience, 15 minutes is more reasonable. Now all the traffic is headed to your new server and since you tested ahead of time (right??) everything is working as it should be.
Now you can migrate your domain names over to the new hosting provider without fear of 48 hours of downtime when your site and apps will be unreachable.