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How to change the color of your BASH prompt

You can change the color of your BASH prompt to green with this command:

export PS1=”\e[0;32m[\u@\h \W]\$ \e[m”

It will change the colour of bash temporarily. To make it permanent then add code in bash_profile page.

vi ~/.bash_profile

and paste above code save the file and you are done.

For other colors please see the attached list:

Color Code
Black 0;30
Blue 0;34
Green 0;32
Cyan 0;36
Red 0;31
Purple 0;35
Brown 0;33
Blue 0;34
Green 0;32
Cyan 0;36
Red 0;31
Purple 0;35
Brown 0;33
Light Color Code
Light Black 1;30
Light Blue 1;34
Light Green 1;32
Light Cyan 1;36
Light Red 1;31
Light Purple 1;35
Light Brown 1;33
Light Blue 1;34
Light Green 1;32
Light Cyan 1;36
Light Red 1;31
Light Purple 1;35
Light Brown 1;33

1. Delete an S3 bucket and all its contents with just one command

Sometimes you may end up with a bucket full of hundreds or thousands of files that you no longer need. If you have ever had to delete a substantial number of items in S3, you know that this can be a little time consuming. The following command will  delete a bucket and all of its content including directories:

aws s3 rb s3://bucket-name –force

2. Recursively copy a directory and its subfolders from your PC to Amazon S3

If you have used the S3 Console, at some stage, you’ve probably found yourself having to copy a ton of files to a bucket from your PC. It can be a little clunky at times, especially if you have multiple directory levels that need to be copied. The following AWS CLI command will make the process a little easier, as it will copy a directory and all of its sub folders from your PC to Amazon S3 to a specified region.

aws s3 cp MyFolder s3://bucket-name/Foldername — recursive

aws s3 sync “My Folder” s3://bukcet-name/“My Folder”

3. Display subsets of all available ec2 images

The following will display all available ec2 images, filtered to include only those built on Ubuntu (assuming, of course, that you’re working from a terminal on a Linux or Mac machine).

aws ec2 describe-images | grep ubuntu

Warning: this may take a few minutes.

4. List users in a different format

Sometimes, depending on the output format you chose as default, when you invoke long lists – like a large set of users – the display format can be a little hard to read. Including the –output parameter with, say, the table argument, will display a nice, easy-to-read table this one time without having to change your default.

aws iam list-users –output table

5.  List the sizes of an S3 bucket and its contents

The following command uses JSON output to list the size of a bucket and the items stored within. This might come in handy when auditing what is taking up all your S3 storage.

aws s3api list-objects –bucket BUCKETNAME –output json –query “[sum(Contents[].Size), length(Contents[])]”

6. Move S3 bucket to different location

If you need to quickly move an S3 bucket to a different location, then this command just might save you a ton of time.

aws s3 sync s3://oldbucket s3://newbucket –source-region us-west-1 –region us-west-2

How to extend disk space in windows 2012

Login to windows. Click on Start run and type cmd.

In windows command prompt.

run diskpart.exe

DISKPART prompt will come.

diskpart >list volume

Above command will show list of volumes.

Select volume volume number

It will select the volume which you want to extend.

extend filesystem

It will extend filesystem size.

Once done. Close the command prompt and refresh windows explorer. If still it is showing old space then try rebooting the server.

dd command to migrate VPS on linux platform.

First create new vps with same configuration on another node. It doesn’t matter new vps is having os or not or you can choose any OS.

Once same configuration VPS setup done then use below command to migrate VPS.

dd if=/dev/guestos/kvm2351_img | ssh 10.10.10.10 “dd of=/dev/guestos/kvm2520_img”

Once migration is completed then try starting VPS on new node.

This post will guide you through how to access the contents of the virtual disk (LVM disk) directly so that you don’t need to boot the VM or when VM is not booting and you want to recover the data(windows or linux)

[[email protected] ~]# lvdisplay | grep centos
LV Path /dev/VolGroup/centos
LV Name centos

We need to create device maps from this LVM device’s partition tables.

kpartx -av /dev/VolGroup/centos

add map VolGroup-centos1 (253:8): 0 9912042 linear /dev/VolGroup/centos 63
add map VolGroup-centos2 (253:9): 0 562275 linear /dev/VolGroup/centos 9912105
add map VolGroup-centos : 0 562212 linear 253:9 9912168

Now we can mount the image and grab any files we may need.

mkdir /mnt/centos

mount /dev/mapper/vbox-centos1 /mnt/centos

Once we are done accessing our files, we can go ahead and unmount the partition and delete the partition mappings.

umount /mnt/centos

kpartx -d /dev/VolGroup/centos