Heartbeat is a daemon that provides cluster infrastructure (communication and membership) services to its clients. This allow clients to know appearance or disappearance of peer processes on other machines and to easily exchange message with them.(Heartbeat - Linux-HA)

Heartbeat clusters work only …

Git is a distributed version control system version control system track history of a collection of files and includes the functionality to revert to another version.

Distributed version control system does not necessarily have a central server which stores data.

User can copy existing repository ( …

When using DRBD, we can grow DRBD disk online so we do not need to disturb the production process we have in the server. The requirement to this feature is the backing block device can be resized online so it is possible to resize the DRBD disk. There are two criterias that must be filled.

1. The …

SMTP use TLS/SSL to secure connection to server and AUTH so only authenticated user can use the SMTP service. This tutorial will show steps to debug SMTP TLS/SSL and AUTH from Linux/Unix terminal.

1. encode your login information in base64, the following perl command which requires MIME::Base64 will …

Linux LVM is a logical volume manager for Linux kernel. Logical volume manager provides method of allocation space in mass storage device that more flexible than traditional partitioning scheme. Logical volume manager can create, resize, and combine partitions, potentially without interrupting …

When using iSCSI and LVM, sometimes we have to manually enable iSCSI disk that used as a physical volume in LVM. This is because LVM service is started earlier than iSCSI service so the iSCSI disk containing the physical volume is not present yet. Solution to this problem is to enable lvmetad in …