https://www.comparitech.com/blog/vpn-privacy/how-to-encrypt-email/

https://saradmin.ru/?p=2851 Protocols IMAP/POP3 Dovecot (http://www.dovecot.org/) IMAP and POP3 server written primarily with security in mind. Cyrus (http://cyrusimap.org/) Intended to be run on sealed servers, where normal users are not permitted to log in. Qpopper (http://www.eudora.com/products/unsupported/qpopper/) One of the oldest and most popular server implementations of POP3. DBMail (https://github.com/pjstevns/dbmail) Fast and scalable email services, storage of mail messages in a […]

First step: use gdisk (or fdisk) #gdisk /dev/sdb and select part code 8e00 – LVM partition we need to prepare our new partitions for LVM #pvcreate /dev/sdb1 Check pvs #pvdisplay Second step: extends the logical partition as far as it can. No need to check and calculate GBs or blocks in various methods. #vgextend /dev/ubuntu-vg […]

https://scottlinux.com/2016/11/22/google-cloud-storage-nearline-personal-linux-desktop-backup/ Backup data to the cloud for cheap with Google Cloud and Nearline storage. I use Google Cloud Storage Nearline to backup my desktop, openmediavault NAS, servers, and more. Here is how I do it! 1. First, sign in here. It may prompt to setup billing if that has not been done: https://console.cloud.google.com 2. Next, […]

https://security.stackexchange.com/questions/59136/can-i-add-a-password-to-an-existing-private-key/59164 Of course you can add/remove a passphrase at a later time. add one (assuming it was an rsa key, else use dsa) openssl rsa -aes256 -in your.key -out your.encrypted.key mv your.encrypted.key your.key the -aes256 tells openssl to encrypt the key with AES256. As ArianFaurtosh has correctly pointed out: For the encryption algorithm you can use aes128, aes192, aes256, camellia128, camellia192, camellia256, des (which you definitely should avoid), des3 or idea remove it […]

https://www.jpablo128.com/how-to-detect-changes-in-a-directory-with-bash/ Sometimes it may be useful to have a script detect whether the contents in a directory have changed since the last time script was run, but excluding some of the files or directories inside. This may be used, among other things, to make backups, for example: there are situations where, instead of doing incremental backups, one […]

https://github.com/RocketChat/docs/tree/master/community-cookbook/remote-video-monitoring

https://zhanghaoblog.wordpress.com/2014/07/09/enable-jmx-for-openfire-3-9-1/