Git Commands

How to create a new branch in Git:

By default, you have one branch, the main branch. With this command, you can create a new branch. Git won’t switch to it automatically – you will need to do it manually with the next comman

git branch branch_name

root@vmlinux:/var/lib/git/.git/devops1# git branch br_work1 root@vmlinux:/var/lib/git/.git/devops1# git branch br_work2 root@vmlinux:/var/lib/git/.git/devops1# git branch br_work3

How to list branches in Git:

You can view all created branches using the git branch command. It will show a list of all branches and mark the current branch with an asterisk and highlight it in green.

git branch

root@vmlinux:/var/lib/git/.git/devops1# git branch 
br_work1
br_work2 
br_work3
* main

How to switch to a newly created branch in Git:

When you want to use a different or a newly created branch you can use this command

git checkout branch_name

root@vmlinux:/var/lib/git/.git/devops1# git checkout br_work1 Switched to branch 'br_work1'

How to create a branch in Git and switch to it immediately:

In a single command, you can create and switch to a new branch right away.

git checkout -b branch_name

root@vmlinux:/var/lib/git/.git/devops1# git checkout -b new_branch5
Switched to a new branch 'new_branch5' root@vmlinux:/var/lib/git/.git/devops1# git branch
br_work1 
br_work2
br_work3 
main
* new_branch5

How to delete a branch in Git:

When you are done working with a branch and have merged it, you can delete it using the command below

git branch -d branch_name

root@vmlinux:/var/lib/git/.git/devops1# git branch -d br_work3 Deleted branch br_work3 (was 6f76b3f).

How to merge two branches in Git:

To merge the history of the branch you are currently in with the branch_name, you will need to use the command below

git merge branch_name

root@vmlinux:/var/lib/git/.git/devops1# git branch
br_work1
br_work2 
main
* new_branch5
root@vmlinux:/var/lib/git/.git/devops1# git merge br_work1 
Already up to date. 
root@vmlinux:/var/lib/git/.git/devops1# git merge br_work2 
Already up to date.

How to show the commit log as a graph in Git:

We can use –graph to get the commit log to show as a graph. Also,

–oneline will limit commit messages to a single line.

git log –graph –oneline

root@vmlinux:/var/lib/git/.git/devops1# git log --graph --oneline
      6f76b3f (HEAD -> new_branch5, main, br_work2, br_work1) commiting some 
text files
     *f21baa3 (origin/main, origin/HEAD) added line in demo.txt
     *8c723ac info1 renamed to demo
     *98e404b created Python_1 folder and moved py files in that folder
     *5e55c5a Python Practise files uploaded
     *3e7a588 first 2 files created

How to show the commit log as a graph of all branches in Git:

Does the same as the command above, but for all branches

git log –graph –oneline –all

How to abort a conflicting merge in Git:

If you want to throw a merge away and start over, you can run the following command:

git merge –abort

How to see remote URLs in Git:

You can see all remote repositories for your local repository with this command

git remote -v

root@vmlinux:/var/lib/git/.git/devops1# git remote -v 
origin	https://github.com/yvsc369/devops1 (fetch) 
origin	https://github.com/yvsc369/devops1 (push)

How to get more info about a remote repo in Git:

Just replace origin with the name of the remote

obtained by running the git remote -v command

git remote show origin

root@vmlinux:/var/lib/git/.git/devops1# git remote show origin
remote origin
Fetch URL: https://github.com/yvsc369/devops1 
Push URL: https://github.com/yvsc369/devops1 
HEAD branch: main
Remote branch: 
main tracked
Local branch configured for 'git pull': 
main merges with remote main
Local ref configured for 'git push': 
main pushes to main (fast-forwardable)

How to push changes to a remote repo in Git:

When all your work is ready to be saved on a remote repository, you can push all changes using the command below

git push

while pushing you will get some type of errors like below

root@vmlinux:/var/lib/git/.git/devops1# git push 
Username for 'https://github.com': yvsc369 
Password for 'https://yvsc369@github.com':
remote: Support for password authentication was removed on August 13, 2021.

remote: Please see https://docs.github.com/en/get-started/getting-started- 
with-git/about-remote-repositories#cloning-with-https-urls for information on 
currently recommended modes of authentication.
fatal: Authentication failed for 'https://github.com/yvsc369/devops1/

Method 1:- Create Public keys and Create SSH Keys in https://github.com/settings/ssh/new

root@vmlinux:/var/lib/git/.git/devops1# ssh-keygen -t rsa 
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa): 
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa. 
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:0bo3C2Q4WlrLrFeQnsR3nRYwO3x2dZHBrwfi3/g2zcU root@vmlinux 
The key's randomart image is:
+---[RSA 2048]	+
|	o.	.o*|
|	o o.	+.|
|	. .. =.oo. .|
|	=..o.+=.	|
|	o=+S. o . + |
|	Bo=.	E|
|	o +.o o	. =o|
|	..	o o	o.=|
|	..	.	oo|
+----[SHA256]	+
root@vmlinux:/var/lib/git/.git/devops1# ls -l ~/.ssh/ 
total 8
-rw------- 1 root root	0 Sep 30 05:45 authorized_keys
-rw------- 1 root root 1675 Sep 30 09:53 id_rsa
-rw-r--r-- 1 root root	394 Sep 30 09:53 id_rsa.pub

root@vmlinux:/var/lib/git/.git/devops1# cat ~/.ssh/id_rsa.pub 
ssh-rsa
AAAAB3NzaC1yc2EAAAADAQABAAABAQDZaPMR0RofHfmlREo7ymKczXGZ7Hsw+wQ85XGUxd3FgZ4ZG
5ojXIHcfFk1Uk2eOSJ0W5tCtLLp/2xPCitr4Nx+Iex/zzeDdCZ2f68zfIkur0B0ZqgSs0Tn2JJTMv WmtS/HymOeJ5dPyOPiL/zEj8Nd28QQcD7c9BS410yCLV2pPdKGxo6VqQHPJn9OJvyvybLcm3wQoNP Ya1bEKNRURNYNv96cQDl+unOf1ymw+vHJvISMJhQx63gvV6Fr4j4sk3gP4y6sY62gHC1fUvgvgjF9 WfhlI1mmQCUHK19jHqvNv1Hd0KM8gPkN5GuP6ThO1deyorNbJQ76KCb45zCXqLF7

Copy the Key Code in Key Section box and add SSH Key mentioned below, and then try to push to github.

Method 2:- Using Access Tokens

Link to create token https://github.com/settings/tokens

Kept for 90 days, you select all options as of now, because we are the beginners and we are at training stage

root@vmlinux:/var/lib/git/.git/devops1# git push 
Username for 'https://github.com': yvsc369
Password for 'https://yvsc369@github.com': ghp_gco8ld6uLMx…DV (token) 
Counting objects: 3, done.
Compressing objects: 100% (3/3), done.
Writing objects: 100% (3/3), 5.00 MiB | 5.25 MiB/s, done. Total 3 (delta 0), reused 0 (delta 0)
To https://github.com/yvsc369/devops1
       f21baa3..6f76b3f	main -> main

How to add a remote repository in Git

This command adds a remote repository to your local repository (just replace https://repo_here

with your remote repo URL)

git remote add origin git@github.com:yvsc369/devops1.git

root@vmlinux:/var/lib/git/.git/devops1# git remote add origin git@github.com:yvsc369/devops1.git

How to pull changes from a remote repo in Git:

If other team members are working on your repository, you can retrieve the latest changes made to the remote repository with the command below

git pull

root@vmlinux:/var/lib/git/.git# git pull 
remote: Enumerating objects: 35, done. 
remote: Counting objects: 100% (35/35), done.
remote: Compressing objects: 100% (31/31), done.
remote: Total 35 (delta 9), reused 23 (delta 3), pack-reused 0 
Unpacking objects: 100% (35/35), done.
From github.com:yvsc369/devops1
* [new branch]	main	-> origin/main
There is no tracking information for the current branch. 
Please specify which branch you want to merge with.
    See git-pull(1) for details. 
        git pull <remote> <branch>
If you wish to set tracking information for this branch you can do so with: 
            git branch --set-upstream-to=origin/<branch> master

How to check remote branches that Git is tracking:

This command shows the name of all remote branches that Git is tracking for the current repository

git branch -r

root@vmlinux:/var/lib/git/.git# git branch -r 
origin/main

How to fetch remote repo changes in Git:

This command will download the changes from a remote repo but will not perform a merge on your local branch (as git pull does that instead).

git fetch

root@vmlinux:/var/lib/git/.git# git fetch root@vmlinux:/var/lib/git/.git#

How to check the current commits log of a remote repo in Git

Commit after commit, Git builds up a log. You can find out the remote repository log by using this command

git log origin/main

root@vmlinux:/var/lib/git/.git# git log origin/main
commit 6f76b3faf315ba6b1cfa301fc4ff3f3549af6f93 (HEAD -> master, origin/main)
 Author: Venkat Chandra <yvsc369@gmail.com>
Date:	Fri Sep 30 07:51:02 2022 +0000

           commiting some text files

commit f21baa39ad597977928f8e678abd9b13b3e481f7 
Author: Venkat Chandra <yvsc.369@hotmail.com>
Date:	Tue Sep 27 12:46:20 2022 +0530

                added line in demo.txt

commit 8c723ac023528cd3d91404d80a22275628d32433 
Author: Venkat Chandra <yvsc.369@hotmail.com>
Date:	Tue Sep 27 12:30:21 2022 +0530

               info1 renamed to demo

How to merge a remote repo with your local repo in Git:

If the remote repository has changes you want to merge with your local, then this command will do that for you

git merge origin/main

How to get the contents of remote branches in Git without automatically merging

This lets you update the remote without merging any content into the local branches. You can call git merge or git checkout to do the merge.

git remote update

How to push a new branch to a remote repo in Git:

If you want to push a branch to a remote repository you can use the command below. Just remember to add -u to create the branch upstream

git push -u origin branch_name

root@vmlinux:/var/lib/git/.git/devops1# git push -u origin new_branch5 
Username for 'https://github.com': yvsc369
Password for 'https://yvsc369@github.com':
Counting objects: 4, done.
Compressing objects: 100% (3/3), done.
Writing objects: 100% (4/4), 1002 bytes | 1002.00 KiB/s, done. 
Total 4 (delta 0), reused 0 (delta 0)
remote:
remote: Create a pull request for 'new_branch5' on GitHub by visiting: 
remote:	https://github.com/yvsc369/devops1/pull/new/new_branch5 
remote:
To https://github.com/yvsc369/devops1
* [new branch]	new_branch5 -> new_branch5
Branch 'new_branch5' set up to track remote branch 'new_branch5' from 'origin'.

How to remove a remote branch in Git:

If you no longer need a remote branch you can remove it using the command below

git push –delete origin branch_name

root@vmlinux:/var/lib/git/.git/devops1# git push --delete origin new_branch5 
To https://github.com/yvsc369/devops1
- [deleted]	new_branch5

How to use Git rebase:

You can transfer completed work from one branch to another using git rebase.

git rebase branch_name_here

Git Rebase can get really messy if you don’t do it properly. Before using this command I suggest that you re-read the official documentation here

How to run rebase interactively in Git:

You can run git rebase interactively using the -i flag.

It will open the editor and present a set of commands you can use.

git rebase -i master

# p, pick = use commit

# r, reword = use commit, but edit the commit message # e, edit = use commit, but stop for amending

# s, squash = use commit, but meld into previous commit

# f, fixup = like “squash”, but discard this commit’s log message # x, exec = run command (the rest of the line) using shell

# d, drop = remove commit

How to force a push request in Git

This command will force a push request. This is usually fine for pull request branches because nobody else should have cloned them.

But this isn’t something that you want to do with public repos.

git push -f

root@vmlinux:/var/lib/git/.git/dev1/devops1# git checkout main 
Switched to branch 'main'
Your branch is up to date with 'origin/main'. 
root@vmlinux:/var/lib/git/.git/dev1/devops1# git push -f 
Username for 'https://github.com': yvsc369
Password for 'https://yvsc369@github.com': TokenPassword
Everything up-to-date