Practical Implementation and Analysis of Git, PAM, Syncthing, and NTP

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Contents
Solution 1.........................................................................................................................................4
Overview of GIT..........................................................................................................................4
GIT process..................................................................................................................................4
Initialization of existing reporting code.......................................................................................4
Cloning of the repository:............................................................................................................5
Add and modify new files............................................................................................................5
Check the status of the local user Git repository.........................................................................5
View the change history..............................................................................................................5
Push local user git repository changes.........................................................................................5
Pull the changes from the master Git repository.........................................................................5
Push and pull fail situation..........................................................................................................5
Permissions on the master Git repository....................................................................................6
Solution 2.........................................................................................................................................7
PAM.............................................................................................................................................7
Question 3........................................................................................................................................9
Syncthing application..................................................................................................................9
Working of syncthing:.................................................................................................................9
Syncthing installation:.................................................................................................................9
Configuring syncthing:..............................................................................................................13
Question 4......................................................................................................................................14
References:....................................................................................................................................16

List of figures:
Figure 1 PAM command.................................................................................................................7
Figure 2 command 1 install curl....................................................................................................10
Figure 3 Command 2.....................................................................................................................10
Figure 4 Command 3.....................................................................................................................10
Figure 5 Command 4.....................................................................................................................11
Figure 6 Command 5.....................................................................................................................11
Figure 7 command 6......................................................................................................................12
Figure 8 GUI of syncthing.............................................................................................................12
Figure 9 part 2 of GUI...................................................................................................................13

Solution 1
Overview of GIT
GIT is an open-source and free version control system. It is a content tracker that can be used to
store the code. The version control system is helpful to maintain the code as it maintains a
history of the changes. It also offers features such as merges and branches. It has a remote
repository. The code is available in each computer of developer thus it is a distributed version
control system. Git is an effective approach. Using this environment, all developer can easily
share the code using the same repository. DVCS is a repository which includes the GIT system.
This repository has synchronization with other remote machines. The main focus of GIT is on
speed and performance. It is designed and developed by Linus Torvalds. This allows the
developers to work with each other. Overwriting of the work is not allowed in the work. It has
commands to store the overall information. The repository is able to maintain the change and
update that without affecting the state of development. It gives a feature of flag cards. Using this
feature history can be pushed to branch members from public members. It is different from
another VCS as it is open source and distributed (Sridhar, 2018).
GIT process
GIT advancement steps:
 Use “git init ” command to upload the directory
 Use “git clone {repo-url}” to clone the repository
 Use “git checkout {branch-name}” and “git branch {branch-name}” for the local repository
branching with remote repositories.
 Use “git push” and “git pull {branch-name}” to edit and push the edits into the repository.
Initialization of existing reporting code
 Make a local directory, the path is “/home/Planets/ktransit”
 Use “git init” for the initiation step
 Use “git add path/to/file/name.ext” to create a commit in the main history
 Use “git commit, git -a commit” for the uploading of main repository and initialization of the
commit (street, 2016).

Cloning of the repository:
SSL codes are helpful in repository cloning. The cloning is the same for the workflow, the
difference is in the content of the local directory and main type that is “git clone
proto://url/repo.git localdir”. Using the Mercury software, cloning process is done as “git
clone /home/Planets/ktransit my-ktransit-clone”.
Add and modify new files
Commit is helpful to amend the new files. Use “git add /path/to/file/name.ext” to add the files.
Recover a particular version of a file
To recover a particular version of the file from local user Git repository it is required that the
main repository world is supported with the primary repository. Use “git checkout {commit-sha |
branch} / path/to/file/name.ext”.
Check the status of the local user Git repository
Use “git status” command is helpful to check or determine the status of the Git repository.
View the change history
Use “git log” command to change in the history of local user Git repository.
Push local user git repository changes
To push the changes of local user git repository back to master git repository using “git push
{remote-name}” command.
Pull the changes from the master Git repository
To pull the changes into the local user Git repository from the master Git repository using “git
pull {remote-name}” command.
Push and pull fail situation
If pull and push functionality get fails because git is not able to merge the differences of a master
repository and local repository then use the /edit/stage/commit workflow to resolve the merge
conflicts. If a merge conflict is encountered then run “git status” command to view which files
need to be resolved. When the merge is about to finish then run “git add” command to inform the

git that they are resolved. Then run “git commit” command to create the merge commit. Also,
avoid 3-way merge instead of this use fast-forward merge.
Permissions on the master Git repository
To allow the users of the research group to clone the master Git repository permissions should be
set by using the “chmod” command. The used command is “chmod -R g+swx ktransit”. Here w
refers to write permission, s refers to inherit state and X refer to the execute permission.

Solution 2
PAM
PAM refers to Pluggable Authentication Module system which offers dynamic authentication
support for the services and applications. Commands such as su, passwd etc. are used for user’s
authentication. It is a modular architecture that offers great flexibility to set the system
authentication policies. It is useful as it offers a basic authentication scheme which is applicable
to a wide range of applications. This also has a fully-documented single library to allow the
developers to create programs without writing authentication schemes. PAM is helpful in
upgradation of the skill ability and a large variety of uses. PAM encourages the utilization of
growth that can liberate from the concerned device. It also encourages development.
Implementation of PAM:
Use “ldd /bin. login |grep libpam” to check the login services.
Figure 1 PAM command
The outcome described shared libraries with the confirmation of login entity process. The PAM
configuration file includes a directive group that defines module and arguments or control with
it. The group of directives has simple syntax to identify the module purpose and the module
configuration settings. The module interface is the first field defined in the PAM configuration
file.
Type is a token in PAM modules that tell the type of authentication that should be used for the
PAM module. The same type of modules can be stacked. Four types recognized by PAM that are
account, password, auth, and session. When called, PAM modules create a fail or success result.
Control flags are responsible to tell the PAM that what is required to be done with the outcome
of PAM modules. A particular order of stacking can be followed by the PAM modules. Some
commonly used flags are required, sufficient, requisite, include, optional etc. For example, the
requisite flag is used to notify the user immediately with a reflection of the first failed message.
PAM has the ability to use module parameters.

PAM modules are the key factor of user authentication. PAM enables programs to authenticate
users transparently. PAM (pluggable authentication module) utilizes the resources and encourage
development (Shamim, 2016).

Question 3
Syncthing application
Data synchronization is very important in the era of a variety of devices. In this kind of situation
use file synchronization programs. Syncthing is also a file synchronization program that is open
source. The key features of syncthing include that it is easy to use as it has CLI as well as GUI. It
has fully automatic data syncing with low interaction. This supports both Linux and windows.
This provides document synchronization between devices with windows or any other operating
system. It is a synchronization tool which is free and allows the user to synchronize files across
all devices such as tablets, desktops, mobile phones, and servers. This acts as an alternate version
of BitTorrent Sync software application. Syncthing technique replaced the cloud and sync
services. It syncs the transmitted data over the internet. In Ubuntu, there are two techniques for
syncthing installation first method is to use snapd tool and second is to use basic commands of
ubuntu. Syncthing is suitable for a wide range of uses. This software is customizable according
to the user’s requirement and it is also programmable. The software is compatible with a variety
of operating systems such as Linux, Solaris, Mac OS X, Windows, and OpenBSD. It has a web
graphical user interface which makes it easy to use and understandable. The installation and
configuration process of syncthing is easy as it does not require advanced configuration options.
Each machine is identified by its unique ID. It does not compromise the privacy and security of
the data. as it does not use a centralized server. Data is stored only on the computer. The
communication is encrypted by using TLS. Encryption is an art of converting readable data into
the non-readable format. For identification of node, it uses the cryptographic certificate. The
package of Syncthing is available on the official repository.
Working of syncthing:
It enables the folder sharing on the computer in a peer-to-peer way. This has no centralized
server or authority for file management. By default, syncthing uses port number 22000 for this or
port number 8384 can be used for the same. As this method needs a firewall port to be opened in
the network for communication with peers which are not on the same network.
Syncthing installation:
Use “apt-get install syncthing” command to install Syncthing.

Figure 2 command 1 install curl
Figure 3 Command 2
Figure 4 Command 3

Figure 5 Command 4
Figure 6 Command 5

Figure 7 command 6
Figure 8 GUI of syncthing