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Firewall configuration RHEL7 - Tech Arkit
Hi friends welcome to Tech ArkIT YouTube channel my name is Ravi in this video session we are going to see how to create Firewall rules are how a Firewall works in Linux.
let's see that so basically most of the times the firewall-cmd we can use command line to create the rules but here which I am going to show you a easy way that you can also use the graphical mode make this a Firewall rules so easy how you can use that
let's see if you want to open a Firewall graphical mode you can also go to Terminal and type firewall-cmd sorry firewall-config it opens a firewall configuration Windows here so from here you can make this configuration changes
you can also open you can also open application from the application if you go to this sundry and say Firewall and this is also open the similar way here we are going to see that the graphical window how it's going to work ok
this is exactly a graphical window here in this firewall-cmd actually there are two configuration one is a runtime configuration next one is an a permanent configuration we're going to see that this is runtime configuration and this is permanent configuration
if you make runtime configuration run time configuration in the sense whenever your machine is on you make the same configuration it affect your rules then whenever you reboot your machine without you reboot your Linux machine the whatever the rules you made its go off but whenever you make on the permanent rule if you restart your machine also is does not go away that's the difference between time configuration and permanent configuration
we're going to see over here and you can see this the connections whatever you have how many connections you have make your connection which connection you would like to make the changes you can also use any Ethernet port ok I can use these zones
you can make multiple zones because this multiple zones can help you out because example say you have in office you can make some office zone over here and right certain and rules
then you go to the public place you make certain rules and you activate the public zone are you can go to home are you can make some related configuration changes on this zone are there rules on this zone then that can affect whenever you activate that zone
like this you can do a number of zones and activate them whenever you need based on your network connectivity are based on your things what you want to activate her what you don't wanted to activate you can use this to activate or not to activate
let over here I am just making the configuration changes over here on the permanent basis on the system again just change the configuration to permanent and I am going to change this zones and I am going to change this configuration in to the public zone
here these are the services what are the service is currently it enabled on the firewall Let's see this IPv6 client http https ssh this are the by default are enabled or I have enabled http and https for making the http web server communication or if you want to enable anything you can just say that tick mark it examples I want to tenable FTP just tick mark it and examples I wanted to enable NFS and ntp something like this that's it
it enabled now you can go to this ports there is no ports are currently enabled if you enable the services also by default enables the ports but you don't need to remember the ports whenever the services are there but which are non standard ports examples that's the standard ports example ssh is 22 but if you do not have any non standard services are non standard ports enable then you have to manually enable over here example same here
I just wanted to specify something like this 18634 and this is a TCP port just I would like to enable over here this port is enable now if you want to enable any protocol level settings I can use this any protocol over here TCP udp icmp if you want to block it or if you want to enable it you can do all this stuff over here
source ports which are the additional sports examples in at the range in Port can accessible we can do from this machine you can add it range of ports example say that I would like to say 1024 to 60004 I don't want to use it or I can enable it like this that all the ports of range of ports will be enabled in the single go like this you can do that
masquarding in the sense this is not just a it's a Linux service or I can say simply say that it's just like NAT settings network address translation settings like you do on the network side in similar way you can do this IP masquerdo go over here if you want to make masquido zones you can make it over here are forwarding this is zone from one IP address to another IP address you can
NAT examples say that none of the machine have some public IP address but that IP address whenever you get the request for their it lands to the other private IP address and which communicate with the public IP address but the end user not only the public IP address but internal redirects to the different IP address that's called Masquerding
we can just use this rules as well but I'm not going to use any Masquerding rules over here
this is called port forwarding port forwarding sometimes very very secure or if you wanted to use this port forwarding method safe and example I am just saying that I am forwarding some of the logs to one of the machine which listens and actually 514 but internally i have another service which is listening on maybe in a non-standard port or maybe different port maybe 9004 or 8004 something like that if you want to forward those logs to this connection you can make use of this forwarding
maybe can say that I'm my standard I don't want to use any standard ports to be communicate on the external face I just wanted to change them to the internally with the service changes can use this port forwarding so that what happens when ever somebody is trying to access your machine with the standard ports they cannot access because it's going to be changed into the different port and the port listening on a different port of Port settings
that's what you can do over here example say that I am just using the source protocol TCP here I am just forwarding 1024 port number 1024 to the destination local forwarding and just using forward to another port maybe can use these different IP address as well maybe I wanted to send this forwarding to the different machine you can also to that this local forwarding Global forwarding in the sense within the local Machine
it's forwarding that 1024 port number to the 2048 port number like this you can use a port rule which can forward this port to this port whenever is your traffic is getting to the 1024 and it's going to be forward to the 2048 this is a port forwarding rule if you want to remove it if you just simply using select and remove it
icmp filters icmp filters are very very useful sometimes its are way if you set one example say i ping to the machine the machine is pinging which means that ok I know that the machine is up and running
but sometimes if you disable this icmp echo or echo request say that when I ping from the remote machine says that I could not able to ping this machine because whenever any icmp packet is getting into this machine say that drop it
that's fine you can make this sometime useful sometimes not because if you say echo request you are going to deny say that some if I ping this machine is going to be not respond to the ping because ICMP filter i put is that do not respond to the any icmp request the remote user may say that the machine is down or the server is down
I am not able to make ping to the admachine you can make based on user security reasons are security measures what you would like to do over here and rich ruls you can write the rich rules to allow ports are the allow a IP address like examples of that I would like to say I don't want to make all each and every IP address to be listed here instead of that we can make enter subnet address over here something like protocol forwarding port forwarding something like that you can do over here
see this you can select any version of over here examples select ipv4 and element with server port or whatever you would like to do a over here example say that port and what you want like write over here which port range I don't want to specify any port range over here maybe some random port
I just selected over here this one what is the action you would like to say you were here and I would like to forward this one are you like to whatever it is or if you want to specify setup IP addresses on here you can set up that IP address is over here if you want to maybe if you want on the Mac address you can add the MAC address to filter if you want to use IP range you can also use this IP range followed by the Subnet Mask ok
and where you wanted to forward or where you wanted to do this port setting forwards you can also use this iP range of IP address all this stuff
this is how we can write the rich rules on the graphical mode you have to understand before what you are making the connections or what you are making the rich rule is all about then make the connection first of all right into the paper and with what you are going to
do over here then make that rich rule
this is the interfaces examples of that if you have multiple interface names if you would like to add into this public zone you can also add interfaces over here but by default I have only one NIC card I have only one interface over here I am not adding any other because I do not have any other to add
sources these are the sources if you like to add or here based on the Mac address IP addresses binding source addresses of information you can add over here MAC Address Ip Address over again and this is how the zones can be
You can see that services directly can allow based on this services if you want to add some standard service he have example say that I have some my naming service name called any application I made it example say that arkit is my service name example specify that my version name is 4 OK short name is nothing description is nothing you can simply Add over here
this port number this service is going to be added over here you can we find that what is the port number example the service is going to be listen on whenever you are adding the rule on the firewall you no need to specify the port number manually you can simply add this --service then provide service name that's it this automatically the service rule is going to be added into the firewall
these are the IPsets you would like to specify the IPsets like example say that this is my certain zone I have this IP range are based on the location based on the work zones you can specify the IP set here this all the configuration we can do from here on the graphical user interface it's very very simple then after that what I have to do is that you have to reload this Firewall settings that is going to be committed changes ok
I have to do this reload this Firewall D then what happened the all the rules what what are the configuration as of now you did it it's going to be effect over here if you do not do reload what happened just going to be not effective no I'm not effective ok
are you can also make the if you made some runtime goes if you like to convert them to the permanent and you can also use these are some time to permanent is going to be to your rules as permanently from the runtime to permanent
that's all you can do the firewall settings are firewall configuration using this GUI tool here
if you would like to make the same related settings you can also use this firewall-cmd is the command which can help you out in making the rules there are many The Other fights audio in the graphical user mode can you make use of the firewall-cmd to make this,nd line only,nd line new stage survival CMD,nd if I would like to make some changes or if I would like to make any Firewall related the rules then you can use this first of all I am going to verify that the firewall status systemctl status Firewall dealer service if the services running you can make any rules if this service is not running you cannot use firewall-cmd which do not affect any configuration changes on equality just I am going to make some firewall-cmd -get default zone I say that what is my currently default zone is anytime you can set one's own as your default is on that what I say that you can make multiple choice but you can activate only one June as your default zone whatever the rules Euro 10 on that particular job will be affected whenever you activate that's all ok simply you can do that firewall-cmd --set default zone equal to whatever zoney would like to whatever the joy you have created that you can make it as default examples I am just making again the public as my default is already there that's why it says that there's always already said to the default now you can see that what is steam I currently active zones get active job there is always one zone that is going to be I can see that are firewall-cmd --version which version currently I'm using at 0.4.4 if would like to a list of the interfaces which I cannot be added into your public zone you can simply use a firewall-cmd --zone which one I would like to use this zone what are the interfaces are there examples with at least interfaces this interface is currently added into the publisher examples if you have different zone you can use that althere is no interfaces handed it to the home zone if you like to add you can aladd using this firewall-cmd command over here --interface equal to Interface name example say that 880 example --zone equal to sorry is equal to home that this is going to add interface 8802 the zone called home firewall-cmd --remove -interface equal to its 08181 equal to how if you want to remove that interface from the zone you can use this,nd to or if you would like to see that how many services are currently there on this Firewall you can use firewall-cmd --services ola services each other name be there on this Firewall it will be listed all over here like this you can add things are remove the things are you can do a rich rules are if you want to import bulk settings or bulk changes to this Firewall you can use this XML file where it is located on the etc ok can match 80c Firewall D and here on this zones exam today that this is called public XML file currently we have made the changes on using the graphical exam model right I guess you can make this XML file and add services and boards settings all the stuff you can load that there's a XML file and reload this Firewall settings that in the single go you can make fire all changes like this you can use your Firewall there are many stuff you can do that example I am going to show you were here is that I am going to make some permanent port forwarding rule from the using The firewall-cmd how we can make that firewall-cmd --permanent I have Network and forward code equal to 4 number which port number if you like to add here ok the port number examples I would like to forward 443 and you can use the: ok and protocol which protocol you would like to use my protocol is TCP and to which port you would like to forward to port and I would like to forward this port to the something like 8080 whenever you are getting the traffic or whenever you are getting the request from port 443 that's going to be transferred to the destination port is 8080 this is the role you can make and ok here we have to add the protocol whenever you add port number that is what this is what the role we have to and there are some this is the photos we have to add ok it's already there and you can have to use firewall-cmd --reload that whatever changes you made it's going to be effective that's about Firewall guys thanks for watching the tune please subscribe the channel for more upcoming videos and courses
RHEL7 Systemctl Explained - RHCSA - Tech Arkit
so how that system in it can be shown on how the system unit can be specified so basically the systemctl command the syntax is over here so here systemctl is the command you have to specify and hear what is the action you would like to do Sudarshan vision sensor you want to do a status on I want to do a restart are you wanted to Airoli Lodha you want just wanted to see the related stuff on the service all this stuff and here you can specify that whatever the name the service name ok and its unique name so any so like this service name its unique name the unit name can be service that surveys are socket or device name or mount name and automount name of name target or path timer a slice a scope there are a number of units files are there in that which you wanted to start example is that you wanted to start only the service then service name that unit name is service start some sockets on that service the service socket name on that service name.net socket you have to be fine so the unit name can be a service socket device mount phone swap target Parth timer please find hope so these are the unit available on the systemctl service so whatever the name you would like to most of the situations we use a bad service most of the situation to use that service or date mornings something like that but these are the you can use to be on this systemctl unit names you can use anything what is your requirement upon so for Service Management task the target unit will be service unit which have unit files with a suffix the services that service or don't forget that device or whatever it is however foremost Service Management commands you can actually leave of the dark service suffix which means that so you can simply leave that service for most of the services you wanted to restart or check the status are you wanted to show them the details about that service which process is using all the related stuff you can do that so let let go ahead and see some examples over here this I would like to see that and status of network service this is the exact the state of output will be in the status of full of put it gives a detailed information that is the service is running successfully are not ok the service is whether it is enabled which means that while restarting your system whether it is enabled or not ok which process ID it is exactly using and which exactly the path of that service file where it is located the script to start that service and what is this listening on and all the details about that can be given on this service status which means that the systemctl status on this any service if you take example for the systemctl status I would like to see that sshd status so the sea for everything which means that which is the dominant is used and which exactly name the path the file path is going to be load over here and whether it is unable to start on the whenever you restart with that it is unable to start on the startup process or not if it is enabled which means that your service is unable to start on the startup reboot the machine ok so this is the demon names related dogs if you can if you want to find some related documentation about that ssh related you can use these commands to do a some documentation stuff over here and which PID currently which is using and which Shield processor CG groups OK then which actually the complete unit is make it into the groove so one service can be done in to the multiple group related information of here so it will give you the all the details like which is running and what is the status of it which port is used listening on Ok that it is accepting all the socket numbers are not all the details it will give you are there I like to say that the systemctl sure ok I can see that internet service over here so I can give you the all the related information about that what it's doing series so what is actually doing audit this configuration and all the stuff it can give you example say that ssh data service which may be serious so what are those all this information is going to be give you in detail information that which is enabled or which is not enabled on which is ok everything will b is going to be give you so if you would like to verify that you're single line that whether the service is active or inactive or whether it is enabled or not enabled you can simply type that systemctl is active and provide the service name say that ok the service is active start on startup you can say that is it enabled essay enabled so like that you can verify any other services if you would like to get the status over here like this so whether it is active maybe can get the different outputs like it is master is is the storm or not stop activated not activated ok those are the information will get on the active status information so if you like to enable any service to start on startup can simply use that systemctl enable and service name the unit name service just I would like to say that table yes it is enabled if you like to restart maybe so if you like to restart these services you can simply simply say that restart over here the service will be restarted but you will not get any output over here you have to verify the status so that it will give the detail information about that whether service is restarted properly or not when it is started so all the details origin reload example say that what the difference between the we start and the reloads for the reloading the since its effect these services changes whatever changes you have changed on that service will be affected but the existing PID will never change if you reload the service so similar way you can see that the PID is 2563 if I would like to reload the sun systemctl service reload over here say kondai dot if you go and verify the status again serious 2563 is the same Id before and now that's what happens when the restart and reload is the differentiation there sorry road in the sense what is the configuration changes without interrupting the service you can apply to the service but if you restart it get interrupted and its PID get Delete completely what are the services what are the existing PID will be killed off and it will be start the new PID for verify that what are the dependency taken simply see that systemctl list dependencies dependencies and provide the name which would like to verify your here you that what are the how many dependencies are there for that series dependencies are there over here so like this you can verify the dependencies and you can verify the system units as well list so these are all the units which is going to be activated are the active currently running all this information on here this many units are currently this is done so there are more than that actually see this there are device anytime there are some different units were here to this most of the in HR Services and you can also see some mounts and can also see some part ok maybe can also see some different series swap and targets rocket also I can see you were here Tera different Unit II simplicity that ok these are the status you can also see that what is mean by the lord and active and serve all this information you can see your here so I should like to see that I'm unit files example that list all the unit files which are currently running or not running in abled not enabled all the information can be shown over here you can see this RP if you can also be filtered further if you like to show only be enabled and disabled want something like that you can also be filtered over here ok maybe the filter can be applied for the baby can also use some great if would like to see only the enabled services over here I can see that this many services not enabled which is going to be very very easy to identify the surface status and you can do that but here in the systemctl you can also set a default target different organisations which would you like to boot example say that I would like to boot into the in multi user target are the the emergency mode or what are the more you would like to MOD examples SCL I are they are what are these thus you wanted to say it you can do that as well examples 8 systemctl get default examples that what is the default target currently have so this is the target currently I have issue like to set a different term target you can also use systemctl and set default say that multi user data get this I would like to set this multi user that target so that whenever I reboot the machine it's going to be a NaCl I mode would like to change this back again to the graphical user mode you can use that graphical so that you can get this so this is how we can change your set default so these are the target she have currently so you can set any in a number of any number of can get to vote your system into the target so suddenly I am using American video currently I am using this graph graphic card at target so that whenever my system is booted it's going to be a run into the graphical mode you can see this this is the graphical mode if a set into the multi user mode it's going to be a RC airplane mode ok so whatever you wanted to say to cancel it but most of the uses a selfie Mania are used to see that the graphical mode so that the basics users can also be happy that whenever you this is a jio instead of CL I so that's what I can say that up buddy fall into the graphical mode that would be a m and great her that would be a useful for you to setup so but here in systemctl they have the different concept called am asking what is mean by the masking the services masking the services in the sense whenever you say that you stop the service are you disable the service the other user can other user can able to enable the service and start the service but if you must the service enable are they cannot start the Service until unless they are not the service so it is over here exam for say that systemctl I just I would like to disable kondadi service over here so that's going to be disabled and I'm going to verify that I'm system is cronbach Kisi that the system is going to be the contact the is disabled so I would like to say that it's going to be start so I stop the service and then just going to see the systemctl status from that data service with says that which is inactive and died which is disabled mode so shall I can see that some of the schedule for the sum of the commands are still trying to stop its related services ok if you would like to mask the service now so now what you can do that if you would like to start the service just see this status over here so which is smart Jism ask if would like to start the service and try or hear what happens servcice fail to start Kondotty Unity smart whenever you marked it so nobody can start the service are unable to service your they cannot do anything until unless they unmask this unmask now you can start the service you can see that is status Kisi that it is running and active like that you can verify you can mark the service whenever you don't need the service or you don't wanted to stop Whenever the service system is restarted are you can tell the other administrators of the other users that do not start the Service until unless they have be continuous requirement and that service to start so this is you can do to the all the services which are not required or which you don't wanted to start the service so that makes a lot of resources savings savings of your hardware resources are its can also be save your system from the unauthorised access using the services are security compromisation all this so that will enable you to make more secure of your system so this is about the systemctl guys you can also use the system CPL command to power off your machine reboot your machine ok even you can do this all to your system so this is how you can do that examples that I would like to reboot this machine so can do that simply a system is going to be rebooted are you can also for of using this systemctl command something like that make use of systemctl so that will be perfect timed use this our future in future so all the best of you thanks for watching stay tune please subscribe the Tech Arkit channel for more upcoming videos and courses
RHEL7 Gain Acces To root User interrupting boot process - Tech Arkit
hi friends welcome to Tech Arkit YouTube channel my name is Ravi. In this video session we are going to see that how to interrupt boot process and get the access to the any Linux machine, whenever you have a physical access to the server.
Let's see this so how you can do that. so first of all here I have the Linux machine switched-on. So i have a physical access to this machine when I click over here so I say that enter and I type the password over here but unfortunately the password is wrong. So I would like to reset this password or I would like to gain the access to the machine. I do not have the password in hand let's do that how you can get it.
so first of all I am going to reboot this machine, click restart, while machine has been restarting so I have to press spacebar to stop over here.
The kernel process stopped over here. here in the kennel step it self what you can do is that so I can simply click are you sick and simply Say e for edit which means that I'm going to edit this kernel lines to interrupt the boot process.
I just edited using the e and go down over here and whereever you see that Linux16 the line ok simply go to the end of that line and add rd.break console equal to tty1 so whenever you add this one what happens so whenever you add this one it says that you are entering your breaking this process and entering into the single user mode.
by entering into the single user mode you get the access to the that machine so which means that you are in the single user mode It does not ask you any username and password just enter into the root directly ok.
so now just press control x now the machine boot process would be interrupted and enter into the single user mode ok now which got into the single user mode directly can see that hash value over here to you which means that which is into root.
type Mount command and see that all this files has been mounted as read only actually. so not mounts really into the rewrite options for here OK.
are else you can also see the mount /sysroot over here already mounted and it is busy looks like ok so maybe you can grep /sysroot ok the root file system has been mounted but which shows here it is that /sysroot is in read only so whenever you have read only file system you cannot edit anything.
it should be read write then only I can write anything on this file system. inorder to gain inorder to convert this into read/write just do this month -o remount,rw /sysroot and read/write this partition re-mount this mount point. With read write access /sysroot
now you can see that using the above command now it is rewrite. just convert this /sysroot into actual root using the convert chroot innocent change chroot /sysroot now it becomes an root now type command called passwd which will ask you for the new password to enter the can now change the password over here so the password authentication has been changed.
now you can rebot the machine but what happened here is that the by default RHEL7 enables the SELinux so without relabling all your selinux policy are the contexts then you can not get the access really to the machine so in order to gain the success and reliable all selinux related stuff then what have to do is that you have to create empty file in the / (slash) so that it relabels automatically so in order to do that create touch / dat auto relabel so be careful because if you mispell or if you do not properly create this file you cannot get the access are you cannot gain access to the machine.
so in order to do that you have to be very careful whenever you are creating this file so confirm that the file has been created and exit from the process whenever you do exit 2 times it reboots the machine it relabels everything from the the contexts of the selinux then it starts the machine then you can enter into the username and password so that you will get the access.
so now your PC has been turned on we can go to the user and type the password so actually reset the password called root user over here and enter the password. that's it you got into the machine see this your machine now you are into root user
that's it so you simply gain this access by interrupting your kernel process whenever you have the physical access to that machine
thanks for watching stay tune please subscribe the channel for more upcoming videos and courses
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RHEL7 Boot Process Step by Step Explained - Tech Arkit
RHEL7 - RHCSA Red Hat Certified System Administrator the first certification for beginners to earn.
A. Understand and use essential tools
1. Access a shell prompt and issue commands with correct syntax
2. Use input-output redirection (>, >>, |, 2>, etc.)
3. Use grep and regular expressions to analyze text
4. Access remote systems using ssh
5. Log in and switch users in multiuser targets
6. Archive, compress, unpack, and uncompress files using tar, star, gzip, and bzip2
7. Create and edit text files
8. Create, delete, copy, and move files and directories
9. Create hard and soft links
10. List, set, and change standard ugo/rwx permissions
11. Locate, read, and use system documentation including man, info, and files in /usr/share/doc
B. Operate running systems
12. Boot, reboot, and shut down a system normally
13. Boot systems into different targets manually
14. Interrupt the boot process in order to gain access to a system
15. Identify CPU/memory intensive processes, adjust process priority with renice, and kill processes
16. Locate and interpret system log files and journals
17. Access a virtual machine's console
18. Start and stop virtual machines
19. Start, stop, and check the status of network services
20. Securely transfer files between systems
C. Configure local storage
21. List, create, delete partitions on MBR and GPT disks
22. Create and remove physical volumes, assign physical volumes to volume groups, and create and delete logical volumes
23. Configure systems to mount file systems at boot by Universally Unique ID (UUID) or label
24. Add new partitions and logical volumes, and swap to a system non-destructively
D. Create and configure file systems
25. Create, mount, unmount, and use vfat, ext4, and xfs file systems
26. Mount and unmount CIFS and NFS network file systems
27. Extend existing logical volumes
28. Create and configure set-GID directories for collaboration
29. Create and manage Access Control Lists (ACLs)
30. Diagnose and correct file permission problems
E. Deploy, configure, and maintain systems
31. Configure networking and hostname resolution statically or dynamically
32. Schedule tasks using at and cron
33. Start and stop services and configure services to start automatically at boot
34. Configure systems to boot into a specific target automatically
35. Install Red Hat Enterprise Linux systems as virtual guests
36. Configure systems to launch virtual machines at boot
37. Configure network services to start automatically at boot
38. Configure a system to use time services
40. Install and update software packages from Red Hat Network, a remote repository, or from the local file system
41. Update the kernel package appropriately to ensure a bootable system
42. Modify the system bootloader
F. Manage users and groups
43. Create, delete, and modify local user accounts
44. Change passwords and adjust password aging for local user accounts
45. Create, delete, and modify local groups and group memberships
46. Configure a system to use an existing authentication service for user and group information
G. Manage security
47. Configure firewall settings using firewall-config, firewall-cmd, or iptables
48. Configure key-based authentication for SSH
49. Set enforcing and permissive modes for SELinux
50. List and identify SELinux file and process context
51. Restore default file contexts
52. Use boolean settings to modify system SELinux settings
53. Diagnose and address routine SELinux policy violations
Edit configuration files faster ever using vi and vim RHCSA
______________________
Text Editores
______________________
Syntax: vi <FileName>
#vi FileName
Insert Mode: You can able to Insert/Write the Data to the Text file.
Command Mode: You can able to copy the text/Delete the text Paste.
EX-Mode: Execute commands, Write/Exit
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Command Mode shortcut
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command mode is default mode to execute text manupalation commands
dd = Delete Line
d5d - will delete 5 lines
5dd - will delete lines
x = Delete Character
nx - delete n characters (Ex. 6x deletes SIX characters)
yy = copy line
y6y - it will copy SIX lines to below
6yy - it will copy SIX lines to below
p = Paste copied lines below the cursor
P = Paste copied line above the cursor
dw = delete single word
u - undo the last action
J - join the line
. - redo
U - undo all changes to the current Line
w - will move to the begining of the next word
nw - will move to nth word begning
b - will move begining of the previous word
nb - will move begining of nth previous words
{ - move backword one paragraph
} - move forward one paragraph
0 - will go to home position
$ - will go to end of the line position
h <-- using h key we can go from right to left direction
l --> using l key we can go from left to right direction
k ^ using k key we can go UP from down
j -- Using j key we can go Down from UP
Shift +G == go to Last line of the file
Shift+h == go to first line of screen
Shift+z == Save & Quit
n = Search Strings from top to bottom
N = Search from bottom to top
%s/Old/New == Replace content from old to new
/StringName == Search Particular Word in the file.
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Insert Mode
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i = Insert Data before the cursor position
I = Insert content starting of the Line
a = It will append current Line characters
A = It will append the characters from end of the Line
o = It will insert a new line below the cursor
O = It will insert a new line above the cursor
s = substitute the stream
r = replace the current character
'home' key to go home of the line
'end' key to go end of the line
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Ex-Mode Shortcut
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Esc key to change the mode to Execute mode
:q = Quit file
:w = write file
:wq = Save& quit.
:q! = quit forcefully
:wq! = Save & Exit forcefully
:1 == go to first line of the File
:set nu == Set the line numbers
:set nonu == Remove Line numbers
:<spesify line number> == Specified Line number.
:r /root/test = copy the content of test file in cursor current position
:r !date = the command output will paste in current cursor position
____________________________
nano Text Editor
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CTRL+g Or F1 = Help
CTRL+x Or F2 = Save File
CTRL+o Or F3 = Write to file to disk
CTRL+j Or F4 = To justify
CTRL+r Or F5 = To insert file text to cursor current position
CTRL+w Or F6 = Search for string
CTRL+y Or F7 = Move to previous screen
CTRL+v Or F8 = Move to the Next Screen
CTRL+k Or F9 = Cut the current and keep into buffer
CTRL+v Or F10 = Uncut/Paste into current file
CTRL+c Or F11 = Display the position of the cursor
CTRL+SHIFT+G = Go to mentioned Line
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