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= LAB OBJECTIVES =
:0. Review SSH setup and remote shell execution
:1. Explore the Fabric Python library and its command line tool "fab".
:2. Create Fabric scripts utilizing Fabric's API to define tasks for the '''fab''' command.
:3. Use the '''fab''' command to execute fabric script to perform pre-defined tasks on remote Linux machines.
== Overview ==:Completing this course will give you Fabric is a Python library and command-line tool for streamlining the prerequisites use of SSH for getting into the DevOps fieldapplication deployment or system administration tasks. A DevOps professional is It has two major components::# a command-line interface program called "fab" that lets you execute arbitrary Python functions :# a system/network administrator with programming skillsset of Python APIs that you can use and call in your Python functions to make executing shell commands over SSH much easier. As an introduction to that field, we will look at : We are going use the Fabric API and its '''Fabricfab''' command to define and execute Python functions (or tasks), to automate interactions with remote Linux machines in this lab. Using Fabric you can automate monitoring, deploying software, and updating many systems at the same time.
== REFERENCE ==
:1. These links are helpful for learning more about Fabric's features:
{| class="wikitable" | style="margin-left:20px; border: 2px solid black;"
| style="border: 2px solid black;" | Category
| style="border: 2px solid black;" | Resource Link
|- style="background-color:white;border:none;"
:[https://www.digitalocean.com/community/tutorials/how-to-use-fabric-to-automate-administration-tasks-and-deployments]
|- style="background-color:white;border:none;"
| style="border: 2px solid black;" valign="top"|
:Official '''Fabric''' website
| style="border: 2px solid black;" valign="top"|
:[http://www.fabfile.org/]
|}
: <font color='blue'>Please note that the version of Fabric installed on matrix.senecacollege.ca for this lab is 1.14 and it supports only Python version 2.</font> The Fabric script files we are going to create in this lab have to meet Python version 2.x requirements. (e.g. print is a keyword, not a built-in function in Python 2.x)
:2. You should have some experience on the following topics in OPS235 and or OPS335. Please review them to prepare for the activities in this lab:
:* create and configure a regular user on a Linux system.
:* configure and manage sudo privilege for a regular user
:* Configure sudoers using the visudo command
:* using the yum command to install, remove, and update rpm packages
:* Retrieve current firewall setting using the iptables -L -n -v command
= INVESTIGATION 1: You should have learned the following topics in OPS235 and or OPS335. Please review them to prepare for some of the tasks in this lab::* How to allow a regular user to run the sudo command. :* man page on sudo:* How to use the sudoers configuration file: /etc/sudoers.The Fabric Environment =
== PART 1 - Configure and test your controller workstation ==: In order to experience Fabric's features in a realistic way, we're going to set up several virtual machinesthis lab you will use your login account on matrix. To begin with they are all going to have the same configurationsenecacollege. Please make sure that each VM has direct network connect with other VMs you wish to control and configureca as your Fabric controller workstation.
: The Fabric package version 1.14.0 has already been installed on matrix.senecacollege.ca. You should have access to the '''fab''' command on matrix. Login to matrix.senecacollege.ca and run the following command to confirm the version of the fabric package:<source lang='bash'>fab --version</source>: Type the following command to get the command line options of the fab command:<source lang= PART 1 'bash'>fab -- Set up your controller help</source>:You should get something similar to the following:<source lang="bash">Usage: fab [options] <command>[:arg1,arg2=val2,host=foo,hosts='h1;h2',...] ...
Options: In -h, --help show this lab you will help message and exit -d NAME, --display=NAME print detailed info about command NAME -F FORMAT, --list-format=FORMAT formats --list, choices: short, normal, nested -I, --initial-password-prompt Force password prompt up-front --initial-sudo-password-prompt Force sudo password prompt up-front -l, --list print list of possible commands and exit --set=KEY=VALUE,... comma separated KEY=VALUE pairs to set Fab env vars --shortlist alias for -F short --list -V, --version show program's version number and exit -a, --no_agent don't use the running SSH agent -A, --forward-agent forward local agent to remote end --abort-on-prompts abort instead of prompting (for password, host, etc) -c PATH, --config=PATH specify location of config file to use your existing vm --colorize-errors Color error output -D, --disable-known-hosts do not load user known_hosts file -e, --eagerly-disconnect disconnect from hosts as soon as possible -f PATH, --fabfile=PATH python module file to import, e.g. '../other.py' -g HOST, --gateway=HOST gateway host to connect through --gss-auth Use GSS-API authentication --gss-deleg Delegate GSS-API client credentials or not --gss-kex Perform GSS-API Key Exchange and user authentication --hide=LEVELS comma-separated list of output levels to hide -H HOSTS, --hosts=HOSTS comma-separated list of hosts to operate on -i PATH path to SSH private key file. May be repeated. -k, --no-keys don'centos7t load private key files from ~/.ssh/ --keepalive=N enables a keepalive every N seconds --linewise print line-by-line instead of byte-by-byte -n M, --connection-attempts=M make M attempts to connect before giving up --no-pty do not use pseudo-terminal in run/sudo -p PASSWORD, --password=PASSWORD password for use with authentication and/or sudo -P, --parallel default to parallel execution method --port=PORT SSH connection port -r, --reject-unknown-hosts reject unknown hosts --sudo-password=SUDO_PASSWORD password for use with sudo only --system-known-hosts=SYSTEM_KNOWN_HOSTS load system known_hosts file before reading user known_hosts -R ROLES, --roles=ROLES comma-separated list of roles to operate on -s SHELL, --shell=SHELL specify a new shell, defaults to '/bin/bash -l -c' --show=LEVELS comma-separated list of output levels to show --skip-bad-hosts skip over hosts that can' as a workstation t be reached --skip-unknown-tasks skip over unknown tasks --ssh-config-path=PATH Path to SSH config file -t N, --timeout=N set connection timeout to N seconds -T N, --command-timeout=N set remote command timeout to N seconds -u USER, --user=USER username to use when connecting to remote hosts -w, --warn-only warn, instead of abort, when commands fail -x HOSTS, --exclude-hosts=HOSTS comma-separated list of hosts to exclude -z INT, --pool-size=INT number of concurrent processes to control other VMs which weuse in parallel mode</source><font color='green'll call workers.><b>Please note and study the following command-line options as they will be used in some of the activities in this lab::# -H, :# -f,:# -i, :# -l, :# --port:# --user:# --initial-sudo-password-prompt </b></font>
== PART 2: Install Connect to VM in myvmlab.senecacollege.ca ==: You should have received an email from ITS containing the following information::* account name: (usually 'student'):* password: (let'fabrics assume it is 'P@ssw0rd'for the following instruction in this lab):* port number for SSH access via myvmlab.senecacollege.ca (e.g. 7200): This VM will be used as the remote Linux machine in our Fabric environment. Login to matrix and try the following SSH command to test the connectivity between matrix and your assignment VM:<pre> [raymond.chan@mtrx-node05pd lab8]$ ssh -p 7200 student@myvmlab.senecacollege.ca student@myvmlab.senecacollege.ca' using yums password: Last login: Fri Jul 3 11:06:24 2020 from mtrx-node05pd.dcm.senecacollege. ca</pre>: Once you are on your VM, try the following commands: hostname, id, and df, and record the results for later comparison with the results of other commands:<source lang='bash'>[student@centos7 ~]$ hostnamecentos7[student@centos7 ~]$ iduid=1002(student) gid=1002(student) groups=1002(student),10(wheel)[student@centos7 ~]$ dfFilesystem 1K-blocks Used Available Use% Mounted ondevtmpfs 878260 0 878260 0% /devtmpfs 889792 0 889792 0% /dev/shmtmpfs 889792 9492 880300 2% /runtmpfs 889792 0 889792 0% /sys/fs/cgroup/dev/mapper/centos-root 38680112 1745524 36934588 5% //dev/sda2 1038336 331228 707108 32% /boot/dev/sda1 204580 11296 193284 6% /boot/efi/dev/mapper/centos-home 18880512 33160 18847352 1% /hometmpfs 177960 0 177960 0% /run/user/1002</source>:Logout from your VM and get back to matrix.:The previous SSH command when executed successfully, created a login shell on the remote machine. If the previous SSH command is followed by a specific bash command, it's installed you should have will be executed on the remote host instead of creating a login shell. Consider the following:<source lang='bash'>[raymond.chan@mtrx-node05pd lab8]$ ssh -p 7200 student@myvmlab.senecacollege.ca 'fabhostname;id;df'student@myvmlab.senecacollege.ca's password:centos7uid=1002(student) gid=1002(student) groups=1002(student),10(wheel)Filesystem 1K-blocks Used Available Use% Mounted ondevtmpfs 878260 0 878260 0% /devtmpfs 889792 0 889792 0% /dev/shmtmpfs 889792 9492 880300 2% /runtmpfs 889792 0 889792 0% /sys/fs/cgroup/dev/mapper/centos-root 38680112 1745608 36934504 5% //dev/sda2 1038336 331228 707108 32% /boot/dev/sda1 204580 11296 193284 6% /boot/efi/dev/mapper/centos-home 18880512 33160 18847352 1% /hometmpfs 177960 0 177960 0% /run/user/1002</source>:The three shell commands: hostname, id, and df were executed sequentially. Compare the outputs above with the previous results when executing the corresponding commands in the login shell.:Please note that you were asked to provide the user' command availables password for every SSH connection.
== PART 2 - Create master Worker image 3: Set up SSH login with public key authentication ==: In order for your controller workstation to automate tasks execution on your VM, you need to configure your VM to SSH public key authentication instead of password authentication. You've done this in both OPS235 and OPS335, and here is a summary on how to do it between your account on matrix and your VM:
: Create a new virtual machineSSH key pair (one private, and allocate one public) under your account on matrix.senecacollege.ca. : Once you have both keys, you can use the '''ssh-copy-id''' command to copy your public key to the student account on your VM, replace the port number with the correct value for it 1GB your VM:<source lang='bash'>ssh-copy-id -i ~/.ssh/id_rsa.pub -p 7200 student@myvmlab.senecacollege.ca</source>: The above command should add the contents of RAM your pub key to ~/.ssh/authorized_keys under your student account on your VM.: Verify and 8GB of disk space. Install a Basic Web Server configuration of CentOS in confirm that your account on matrix can SSH to your VM using the same CentOS as 'student' without prompting for a password:<source lang='bash'>[raymond.chan@mtrx-node05pd lab8]$ ssh -p 7200 student@myvmlab.senecacollege.caLast login: Fri Jul 3 12:46:19 2020 from mtrx-node05pd.dcm.senecacollege.ca[student@centos7 ~]$ exitlogoutConnection to myvmlab.senecacollege.iso file you used for your first machine in this courseca closed.
=INVESTIGATION 2 - Running the fab command in ad-hoc mode =: The fab command relies on SSH to make the connection to the remote machine before executing the intended commands. The fab command can run in ad-hoc mode:<source lang= Set up 'bash'>fab [options] -- [shell commands]</source>: When running the fab command in ad-hoc mode, it is very similar to running the SSH key login with commands attached at the end. == PART 1: running non-privileged shell commands on remote machines ==: In order the following example, we use the '''fab''' to execute the "date", "hostname", and "id" command remotely on our VM. Try the following ad-hoc fab commands and record their results for later use, replace the port number with the correct value for an automated system to be able to connect to your VM and administer it :<source lang='bash'>[raymond.chan@mtrx-node05pd lab8]$ fab --host=myvmlab.senecacollege.ca --port=7200 --user=student -- you will need to be able to connect to it using SSH keys'date;hostname;id'[myvmlab.senecacollege. Youca] Executing task 've done this in both OPS235 and OPS335<remainder>'[myvmlab.senecacollege.ca] run: date;hostname;id[myvmlab.senecacollege.ca] out: Fri Jul 3 13:05:39 EDT 2020[myvmlab.senecacollege.ca] out: centos7[myvmlab.senecacollege.ca] out: uid=1002(student) gid=1002(student) groups=1002(student),10(wheel)[myvmlab.senecacollege.ca] out:
== PART 2: '''** Optional **''' Make four clones of the master worker image you've just created. Then make sure running privileged commands on remote machines ==: We say that each of them has a unique IP address. That's all you're required running an ad-hoc fab command is very similar to change manually. All the other configuration on SSH command with shell commands attached at the workers (inlcuding the hostnames) will be set by Fabricend. Normally you would have some kind of automation doing all this cloning and IP address assignment as wellLet's try both with privileged commands, but we don't have time for that this semesterlike the "yum" command.
</source>
: Using the "yum" command to query rpm package doesn't need special privilege, however, it does when you try to install or remove rpm packages.
: Your "student" account on your VM was configured to allow you to run the "sudo" command to perform software management using the "yum" command. Let's login to your VM and try the following "sudo" command to install and then remove the "tree" rpm package:<source lang='bash'>
[raymond.chan@mtrx-node05pd lab8]$ ssh -p 7200 student@myvmlab.senecacollege.ca
Last login: Fri Jul 3 16:51:07 2020 from mtrx-node05pd.dcm.senecacollege.ca
[student@centos7 ~]$ sudo yum install tree -y
[sudo] password for student:
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: less.cogeco.net
* extras: centos.mirror.colo-serv.net
* updates: mirror.calgah.com
Resolving Dependencies
--> Running transaction check
---> Package tree.x86_64 0:1.6.0-10.el7 will be installed
--> Finished Dependency Resolution
Total download size: If you did all the setup right and you try to execute the command above 46 kInstalled size: 87 kDownloading packages:tree-1.6.0- you will get a password prompt10. Read the prompt carefully and see who's password it prompts youel7. If it is not the same as your [seneca_id], try to fix it by adding the following line to before the first '''def''' line your fab filex86_64.rpm | 46 kB 00:00:00Running transaction checkRunning transaction testTransaction test succeededRunning transaction Installing : tree-1.6.0-10.el7.x86_64 1/1 Verifying : tree-1.6.0-10.el7.x86_64 1/1
Installed:<source lang="python">env tree.user = '[seneca_id]'</source>x86_64 0:1.6.0-10.el7
Complete![student@centos7 ~]$</source>:That should have workedPlease note that when you run the "sudo" command the first time, and it asks youfor the user's password (i.e. user student's password). Let's now remote the "tree" package:<source lang='bash'd get output like >[student@centos7 ~]$ yum remove tree -yLoaded plugins: fastestmirrorYou need to be root to perform thiscommand.[student@centos7 ~]$ sudo yum remove tree -yLoaded plugins: fastestmirrorResolving Dependencies--> Running transaction check---> Package tree.x86_64 0:1.6.0-10.el7 will be erased--> Finished Dependency Resolution
Installed size: In the above you have87 kDownloading packages::* Lines with an IP address telling you which worker the output is for/from.Running transaction checkRunning transaction testTransaction test succeededRunning transaction Erasing :* Messages from the controller (etree-1.g6. "Executing task0-10.el7..", and "runx86_64 1/1 Verifying : tree-1.6.0-10.")el7.:* Output from the worker ("out: ..."):* Output on the controller from your fab file ("worker1" which came from the "print()" call)x86_64 1/1
Removed:You should get used to the above tree. It's a lot of output but it's important to understand where every part is coming from, so you are able to debug problems when they happenx86_64 0:1.6.0-10.el7
Complete![student@centos7 ~]$</source>: The above tests confirm that the student user is allowed to run the yum command to install and remove rpm package. Now let's logout from the VM and go back to matrix. On matrix, try to run the sudo command using SSH:<source lang== Part 2'bash'>[student@centos7 ~]$ exitlogoutConnection to myvmlab.senecacollege.ca closed.[raymond.chan@mtrx-node05pd lab8]$ ssh -p 7211 student@myvmlab.senecacollege.ca "sudo yum install tree -y"sudo: no tty present and no askpass program specified[raymond.chan@mtrx-node05pd lab8]$</source>: Set The above error indicated that you need a tty for the SSH session to prompt you for the sudo password. Please look up web server ==the ssh man page to find out the option which turn on a tty for the SSH session.
=== Run the privileged yum command on remote machine using ad-hoc fab command ===:Let's pretend that we needed to deploy a web server try the corresponding ad-hoc fab command on several machines. Weyour VM:<source lang='bash'll set up a simple example of such a deployment here.>fab --host=myvmlab.senecacollege.ca --port=7200 --user= Install Apache ===student -- 'sudo yum install tree -y'</source>:Add a setupWebServer() function Type in your user student's password when prompted for "sudo password", the yum install command to your python file: install the tree rpm package should be executed successfully. If the tree rpm package is already installed, you can remove it with the following ad-hoc fab command:<source lang="python"'bash'># Will set up a working web server with a prefab --host=myvmlab.senecacollege.ca --port=7200 --user=student -built websitedef setupWebServer(): run("hostnamectl set-hostname www") run("'sudo yum install httpd") run("systemctl enable httpd") run("systemctl start httpd")remove tree -y'
</source>
: Try remove the "tree" rpm package with the appropriate ad-hoc fab command.
= INVESTIGATION 3:Note Running the fab command in script mode =: From investigation 2, we can see that each call running '''fab''' in ad-hoc mode is quick, straight forward, and easy. However, the rich output generated can not be easily captured and processed. If you have a need to capture and process the output generated by the commands executed on the remote machines, the solution is to "run()" will run a the '''fab''' command on in script mode.: The first step in running the worker'''fab''' command in script mode is to create a fabric script file. In this function we set : Let's start with a simple fabric script file to demonstrate some basic concepts that use the hostname of API from the machine Fabric python library.: On matrix, cd to "www", install Apache, enable the Apache service, your lab8 directory and start that service now. Pretty create a simple commandsfabric script file named '''fabfile.py''' (this is the default filename used by the fab command when you invoke it without the '-f' optino):
== PART 1:If you try Non-privileged task example =====Create non-privileged tasks: Getting the hostname of remote machines===: Add the following contents to run it the same way as beforedefault fabric script called "fabfile.py" in your lab8 directory:<source lang="python">from fabric.api import *
# Define the task to get the hostname of remote machines:You'll find that yum prompts you to answer questions, which you don't want to do in an automated environment. And also yum prints too much output, which also isn't helpful in an automated environment. We'll fix it by adding two switches to yumdef getHostname(): name = run("-yhostname" and ) print("-d1The host name is:":,name)</source>
:Notice also that all of To check for syntax error in the four commands can be fabric script, run as many times as you want, the result will be following command in the lab8 directory where it contains the samefabric script named "fabfile. This is not always so easypy":<source lang="bash">fab -l</source>: you should get a list of tasks defined in your fabfile.py:<source lang="bash">[rchan@centos7 lab8]$ fab -lAvailable commands:
getHostname</source>:At this point if you log in To perform the task of getHostname on your VM (replace with the actual port # for connecting to worker1 - you should see a new hostnameyour VM), and httpd installed and running (try with run the fab command on matrix:<source lang="systemctl statusbash")>[raymond.chan@mtrx-node05pd lab8]$ fab --hosts=myvmlab.senecacollege.ca --port=7200 getHostname[myvmlab.senecacollege.ca] Executing task 'getHostname'[myvmlab.senecacollege.ca] run: hostname[myvmlab.senecacollege.ca] out: centos7[myvmlab.senecacollege.ca] out:
</source>
: Notice that there is no need to specify the user name at the '''fab''' command line since we defined it in the fabric script file (env.user = 'student'). Also notice that we can capture the host name returned from the "hostname" command and print it out together with an descriptive text in a line.
:There is something weird in In the code above that you havenexecuted 't seen before but it's required for some uses of Fabric: the 'fab''with''' statementcommand, the fab program imports the fabric script named "fabfile.py" and execute the getHostname function on the VM connect at port 7200 on myvmlab.senecacollege.ca. Note that the port number for your first will likely be of a different value.
:The problem is that separate '''run''' commands each If you did all the setup right and you got a password prompt when execute in a brand new sessionthe above command, each with its own shellread the prompt carefully and see who's password it was prompting you for. They are If it is not like separate lines for the user student, verify that you have the following line in a single shell script even though they look like they should beyour fabfile.py and you can ssh to your VM as the user student without password:
:That means if you run a cd command and then a tar command separately - the tar command will not run in the directory where you think it will<source lang="python">env. In order to fix this you have to nest commands inside a user = 'student''with''' - it's like a '''run''' but with persistant results.</source>
:The code we added to In the function will cd to above output from the '''fab''' command, you have::* Lines with the FQDN of the default web site directory remote machine you are working on .:* Messages from the workercontroller workstation (e.g. "Executing task...", upload your web contents tarball and "run: ...").:* Output from your controller to that directory the remote machine ("out: ..."):* Output generated on the worker, extract it, and delete controller workstation from your fab file (the tarball.print statement)
:After You should get used to the above messages from the '''fab''' command. It's a lot of output but it's done - important to understand where every part is coming from, so you should have a working web server and simple website on your worker1are able to debug problems when they happen.
== PART 2:Except you won't be able Privileged Tasks Examples =====Creat privileged tasks: install and remove rpm package on remote machines===: Add the following two new functions to access it because the end of the firewallfabric script "fabfile. Wepy" in your lab8 directory:<source lang='ll deal with that in the next section.bash'>
def installPackage(pkg== Part 2'dummy'): Set up the firewall cmd ='yum install ' + pkg + ' -y' status =sudo(cmd) print(status)
def removePackage(pkg): Recall if pkg == '': cmd = 'yum remove dummy -y' else: cmd = 'yum remove ' + pkg + ' -y' status = sudo(cmd) print(status)</source>: Note that both functions take one function argument in our OPS courses we've been using iptables instead of firewallddifferent ways. However, which if no function argument is installed by passed when calling the function, both will default to a string value of "dummy". Both functions call the sudo() from the fabric.api to execute the command contained in CentOSthe "cmd" object on the remote machine via sudo. Let's make sure that our workers have that set up : To check for any syntax error in your updated fabric script, run the following command in the same directory as well. In the same '''fabfile.py:<source lang='bash'>fab -l</source>: You should get a list of tasks defined similar to the following:<source lang=' youbash've been using all along, add a new function like this>[raymond.chan@mtrx-node05pd lab8]$ fab -lAvailable commands:
</source>
: If you only need to connect to the same remote machine, you can specify the host and port number in the fabfile.py to save some typing when executing the fab command. Add the following two lines after the env.user line in your fabfile.py:<source lang='bash'>
env.port = '7200' # <-- please replace with the actual value of your VM's port number
env.hosts =['myvmlab.senecacollege.ca']
</source>
: You can also store the user's password in this file so that it will respond to the "sudo password" prompt for sudo() call. It is not safe to do so as you can configure the sudo module on the remote machine not to ask for sudo password.
: Now you can run the fab command without the "--host" and "--port" option.
: Run the following two fab commands, note the results and compare their difference:<source lang='bash'>
fab installPackage
fab installPackage: That should by now look prett obvious. On tree</source>: Run the worker you're going to uninstall firewalld, install iptablesfollowing two fab commands, note the results and make sure that the iptables service is running.compare their difference:<source lang='bash'>fab removePackage
fab removePackage: Execute the function for worker1 and double-check that it worked.tree</source>
==Part 2: Create remote task for updating rpm packages = Allow access =: Add a new function called "updatePackage" to your fabfile.py according to Apache through the firewall =following requirements::* Accept optional function argument as the rpm package name:* If no function argument was given when called, default to all the packages installed: The output of the updatePackage when executed, should produce similar output as shown below::1. Update a single package:<source lang='bash'>fab updatePackage:tree</source>: Sample output:<source lang='bash'>[raymond.chan@mtrx-node05pd lab8]$ fab updatePackage:tree[myvmlab.senecacollege.ca] Executing task 'updatePackage'[myvmlab.senecacollege.ca] sudo: yum update tree -y[myvmlab.senecacollege.ca] out: sudo password:[myvmlab.senecacollege.ca] out: Loaded plugins: fastestmirror[myvmlab.senecacollege.ca] out: Loading mirror speeds from cached hostfile[myvmlab.senecacollege.ca] out: * base: less.cogeco.net[myvmlab.senecacollege.ca] out: * extras: centos.mirror.ca.planethoster.net[myvmlab.senecacollege.ca] out: * updates: less.cogeco.net[myvmlab.senecacollege.ca] out: No packages marked for update[myvmlab.senecacollege.ca] out:
Loaded plugins: The default setup of iptables also doesn't allow access to our web serverfastestmirrorLoading mirror speeds from cached hostfile * base: less.cogeco.net * extras: centos.mirror.ca. We'll need to add some more to our function to allow itplanethoster. This would probably make more sense in setupWebServer() but net * updates: less.cogeco.netNo packages marked for now let's put it into setupFirewall():update
Done.Disconnecting from myvmlab.senecacollege.ca: <source lang="python"> run("iptables -I INPUT -p tcp --dport 80 -j ACCEPT")7200... done. run("iptables[raymond.chan@mtrx-save > /etc/sysconfig/iptables")node05pd lab8]$
</source>
</source>
: The following output had been trimmed, only showing the first few lines:<source lang='bash'>
[myvmlab.senecacollege.ca] Executing task 'updatePackage'
[myvmlab.senecacollege.ca] sudo: yum update -y
[myvmlab.senecacollege.ca] out: sudo password:
[myvmlab.senecacollege.ca] out: Loaded plugins: fastestmirror
[myvmlab.senecacollege.ca] out: Loading mirror speeds from cached hostfile
[myvmlab.senecacollege.ca] out: * base: less.cogeco.net
[myvmlab.senecacollege.ca] out: * extras: centos.mirror.ca.planethoster.net
[myvmlab.senecacollege.ca] out: * updates: less.cogeco.net
...
Verifying : Test your new setupFirewall function on worker1, and make sure it opens access to Apache but does not create duplicate rules every time it's runsystemd-219-73.el7_8.5.x86_64 53/54 Verifying : systemd-libs-219-73.el7_8.5.x86_64 54/54
Installed: After completing all the previous parts of the lab kernel.x86_64 0:3.10.0- you should have a working fabfile1127.py with two working functions: setupFirewall() and setupWebServer()13.1.el7
= Final Task - Apply fabfile.py to your VM on myvmlab Lab Exercise: Create a Fabric task called makeUser() =: Since your account on your vm on myvmlab is a regular user with Study the Fabric API run(), sudo privilege. You need (), and put() and utilize them to make create a new task called makeUser(): The makeUser() function should perform the following changes to your fabfile.py before applying it to your vm on myvmlab::* Change envcreate a new user called "ops435p" with home directory "/home/ops435p".user from 'root' :* add it to your account on your vm in myvmlabthe sudo group called "wheel".:* Change all ask your professor for a ssh public key and add it to the file named "authorized_keys" in the commands ~ops435p/.ssh directory. Make sure that need super user privilege from calling you set the proper permissions on both the run() function to instead calling directory ~ops435p/.ssh and the sudo() functionfile "~ops435p/.ssh/authorized_keys.: Test Add the makeUser() to your updated final version of fabfile.py until you get . :Run the same result as when you apply it to new task makeUser() on your own worker VM.:Verify and confirm that your new makeUser() task is working correctly.
= LAB 8 SIGN-OFF (SHOW INSTRUCTOR) =
:'''Have Ready to Show Your Instructor:'''* Complete all the parts of the lab and show upload the version of your fabfile.py which works on your vm on myvmlabto Blackboard by the due date. = LAB REVIEW =
[[Category:OPS435-Python]][[Category:rchan]]
