• ssh how to verify your host key / avoid MIM attacks

    SSH helps keep us secure in many ways, one of those is the host-key fingerprint which is unique. If you have been connecting to an SSH server that you've made no changes to and suddenly ssh warns that the key doesn't match then you have a problem. But how about connecting to an existing server for the first time on a new machine or client? A lot of new clients calculate it using an SHA256 hash but it is not as easy on your host machine to produce the sam........
  • How to encrypt your SSH private key file id_rsa

    ssh-keygen -p -f /path/to/your/id_rsa Enter new passphrase (empty for no passphrase): After that your rsa private key will be encrypted which is a layer of protection and security in the event that somehow someone acquires your key and tries to access servers that the key is authorized on.........
  • systemd management using systemctl and journalctl to check systemd logs

    systemd is like the service manager for your Centos and other modern Linux distributions (including Debian/Mint/Ubuntu) allows you to enable services, stop them, restart them, check their status and even reboot your system. The key commands or arguments you will use with systemctl are the following: Unit Commands: list-units [PATTERN...] List loaded units &nbs........
  • VMWare ESXi 6.7 SSH/PowerShell CLI Commands

    [root@localhost:~] BootModuleConfig.sh echo host-ind nfcd........
  • Firefox errors Unable to generate public/private key pair. (Error code: sec_error_keygen_fail)

    Your firefox is out of date if you get errors like below: Secure Connection Failed ........
  • Cygwin and crontab backups via ssh/scp/rsync

    Install the "Editors" and "Net" groups that will give you rsync, ssh, ssh-keygen and cron. The trickiest thing that I keep forgetting about each time is you have to run "cron-config" which adds the cron service to Windows, and without doing that obviously no cron jobs will be run thus making automatic backups impossible. Warning about rsync/cygwin and using the -a archive switch. It's a good thing I caught this because it doesn't work ri........
  • WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! "IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY! Someone could be eavesdropping on you right now (man-in-the-middle attack)! It is also possible that the RSA host key has just been changed. The f

    @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY! Someone could be eavesdropping on you right now (man-in-the-middle attack)! It is also possible that the RSA host key has just been changed. The fingerprint for the RSA key sent by th........
  • SSH Automatic/Passwordless Logon - Setup Public Key Encryption In Single Command

    This is a very simple solution, but most guides out there make you login twice (once to scp the key) and once to put the key in authorized_keys. There's no need for that. If you don't already have a ~/.ssh/id_rsa.pub just type "ssh-keygen -t rsa" and keep hitting enter until it's done :) Just use this code to easily enable passwordless login with SSHD key=`cat ~/.ssh/id_rsa.pub`;ssh user@ "echo $key >> ~/.ssh/auth........
  • PHP cannot access /usr/bin/openssl

    PHP cannot access /usr/bin/opensslI have verified the username that runs the process is able to access /usr/bin/openssl and it does exist but the PHP script is saying it doesn't exist: [code:1:1fd0f3abbe] if (!file_exists($OPENSSL)) { //echo "ERROR: OPENSSL $OPENSSL not foundn"; }[/code:1:1fd0f3abbe] I don't get itI can clearly see the contents of /usr/bin by using the PHP system fu........
  • SSH automatic login without password

    SSH automatic login without passwordlocal> ssh-keygen -t rsa -f .ssh/id_rsa -t is the encryption type -f tells where to store the public/private key pairs. In this case, the .ssh directory on home is being used A password will be asked; leave this part blank, just pressing Now, go the .ssh directory, and you will find two new files: id_dsa and id_dsa.pub. The last one is the public part. Now, copy the public key to the serv........
  • Linux/Unix Open SSH Login Without Password Key Exchange including Debian, Redhat, Fedora, Ubuntu, BSD etc..

    In those 4 simple commands you can setup mutual key exchange between two sshservers by using a single login shell session and single window. *Just change the IP address examples of ( to the target of your mutual key exchange. It doesn't matter if the server is on a LANor WAN(well unless the server is behind a firewall and you cannot SSHinto it).........
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