dmeventd - Linux
Overview
dmeventd is a daemon that monitors Device Mapper Event (DME) devices and controls their corresponding DME targets. It provides an interface for applications to create, destroy, and modify DME devices and targets, allowing for dynamic management of disk and storage configurations.
Syntax
dmeventd [options]
Options/Flags
- -f, –foreground
Run in the foreground without daemonizing. - -h, –help
Display command help and exit. - -l, –log-level
Set the logging level (error
,info
,debug
). Defaults toinfo
. - -p, –pid-file
Specify the path to the PID file. Defaults to/var/run/dmeventd.pid
. - -s, –socket
Specify the UNIX socket path to listen on for client connections. Defaults to/var/run/dmeventd.sock
.
Examples
- Create a DME device and target:
dmeventd --create-device /dev/dm-test --create-target /dev/sdc1
- Destroy a DME device and target:
dmeventd --destroy-device /dev/dm-test --destroy-target /dev/sdc1
- Modify a DME target:
dmeventd --set-target /dev/dm-test --offset 1024 --size 102400
Common Issues
- dmeventd fails to start: Check if the specified UNIX socket file exists and has the proper permissions.
- DME devices or targets cannot be created: Ensure that the kernel module
dme
is loaded and the necessary device drivers are installed.
Integration
dmeventd can be integrated with other commands and tools for advanced management tasks, such as:
- lvm: Use dmeventd to manage logical volumes on top of DME targets.
- cryptsetup: Encrypt DME targets using cryptsetup for secure data storage.
Related Commands
dmsetup
: Manage Device Mapper devices directly.pvcreate
,vgcreate
,lvcreate
: Create and manage logical volumes using the LVM stack.