How to use the ssh-keygen command in Linux

Editor to share with you how to use the ssh-keygen command in Linux, I believe most people do not know much about it, so share this article for your reference, I hope you can learn a lot after reading this article, let's go to know it!

The Linux common command ssh-keygen command is used to generate, manage, and transform authentication keys for "ssh". It supports both RSA and DSA authentication keys.

Command format syntax ssh-keygen [- Q] [- b bits]-t type [- N new_passphrase] [- C comment] [- f output_keyfile] ssh-keygen-p [- P old_passphrase] [- N new_passphrase] [- f keyfile] ssh-keygen-I [- f input_keyfile] ssh-keygen-e [- f input_keyfile] ssh-keygen-y [- f input_keyfile] ssh- Keygen-c [- P passphrase] [- C comment] [- f keyfile] ssh-keygen-l [- f input_keyfile] ssh-keygen-B [- f input_keyfile] ssh-keygen-D reader ssh-keygen-F hostname [- f known_hosts_file] ssh-keygen-H [- f known_hosts_file] ssh-keygen-R hostname [- f known_hosts_file] ssh-keygen-U reader [- f input_keyfile] Ssh-keygen-r hostname [- f input_keyfile] [- g] ssh-keygen-G output_file [- v] [- b bits] [- M memory] [- S start_point] ssh-keygen-T output_file-f input_file [- v] [- a num_trials] [- W generator] Common options-b: specify key length -e: read the openssh private key or public key file;-C: add comments;-f: specify the file name to save the key;-I: read the unencrypted ssh-v2-compatible private / public key file and then display the openssh-compatible private / public key on the standard output device;-l: display the fingerprint data of the public key file;-N: provide a new password;-P: provide (old) password;-Q: silent mode -t: specifies the type of key to create. Refer to the example to create a default key

[root@localhost ~] # ssh-keygenGenerating 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:QfclO+AvXZ/O6vGNfzo4P2pftiHRoKG2fgc5p9bvu1o root@localhost.localdomainThe key's randomart image is:+--- [RSA 2048]-+ |. O. . | |. O o + | |. .. +. | | ooooooooooo.. | | So..+. | O. | |. . =. + | |. * + Eo | |. + + oO+= | | .o. + OO%* | +-[SHA256]-+ [root@localhost ~] # specify the type of key to be created

[root@localhost] # ssh-keygen-t rsaGenerating public/private rsa key pair.Enter file in which to save the key (/ root/.ssh/id_rsa): / root/.ssh/id_rsa already exists.Overwrite (YPIO)? YEnter 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:nTaoqOxlG6IQQ2zDTMvSk2EON+4tLrYqPy7IBrstoy4 root@localhost.localdomainThe key's randomart image is:+--- [RSA 2048]-+ |.. = | | * B.+ | | .x * | +.. oo. | | o o. S = |. +. . . . . | | * oo =. | | | EBo= o | |% @ B.. | | +-[SHA256]-+ [root@localhost ~] # use the-t parameter to create a specified key type and add comments |

[root@localhost] # ssh-keygen-t rsa-C "deng@qq.com" Generating public/private rsa key pair.Enter file in which to save the key (/ root/.ssh/id_rsa): / root/.ssh/id_rsa already exists.Overwrite (ymen)? YEnter 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:Wx3MWwj36fwhcnb6hjdIIJ3SUggCLcmFq62Earqy2E0 deng@qq.comThe key's randomart image is:+--- [RSA 2048]-+ |.. * o. O. | | =. . * o. | | o + * + | |. + * * | |. O S =. + + oo | | .o. O +. +.. | | o. E. . o. | | + o. O. + | | Oo. . O.. | +-[SHA256]-+ [root@localhost ~] # read the private key or public key file of openssh

[root@localhost ~] # ssh-keygen-eEnter file in which the key is (/ root/.ssh/id_rsa):-BEGIN SSH2 PUBLIC KEY-Comment: "2048-bit RSA, converted by root@localhost.localdomain from O" AAAAB3NzaC1yc2EAAAADAQABAAABAQCyQ/iZYPZHH7+4Gcfq259xChnidsf25piKsnRi+o/XZcD0s9QL8oX24OuX5pPQcmfD6Rw6sQCrTy66LrSw2NmPpKc0XdUbXEkLYBN4d3SY+ZLT3Ot8L6jaDmwgXsBu8lTXzAEWLm+16RXAZAB/27ohi48PfcIDYyeJ1JDpieCJ1/a/KrR9V4erWVBt/ZE8KoC0MTQlUn7H3oABVS9O6sdY4dYc/T9l33EbqZMc2feYZnuWtrPdrYfz37C+kzg3ZrDojGXtiWk1p/PG5KoAH6GzuYYIuMtrUTnadRv4wZo29RF+n5Ty8HEeYqSceHWWvwJjqnpqj9cgeNQvq6E3PJbD---- END SSH2 PUBLIC KEY-[root@localhost ~] # quiet mode generation key pair

[root@localhost] # ssh-keygen-Q-t rsaEnter file in which to save the key (/ root/.ssh/id_rsa): / root/.ssh/id_rsa already exists.Overwrite (YPAPO)? YEnter passphrase (empty for no passphrase): Enter same passphrase again: [root@localhost ~] # these are all the contents of this article entitled "how to use ssh-keygen commands in Linux". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!