The following material is intended to serve as an example and a reference guide to help spot when disk input/output errors coming from the hardware are creating problems for the backup agent, with somewhat varying error messages shown in the backup console and in PCS logs. The existence of hardware disk errors is not only a problem for the creation of backups - it can pose a hidden yet significant danger to the stability and operability of the customer's machine, and can easily lead to data loss - so spotting those on time can be crucial.


  1. You're using cPanel or Plesk integration and attempt to install Agent on AlmaLinux,
  2. Installation fails with:

    NotSupportedLinuxDistrError: Unsupported linux distributive "almalinux"


cPanel and Plesk don't support agent installation on AlmaLinux.


Starting from version 1.6.5, Acronis Backup plugin supports the AlmaLinux OS. Please use the latest version. Backup fails with errors "Failed to commit operations" and "Internal error: different hash after rebackup"

Compiling the necessary SnapApi modules for Acronis backup software for Linux

Download Linux components from Acronis website

How to create a Linux System Report

Starting from version C21.12, Acronis Cyber Protect Cloud has a dedicated Agent for backing up MySQL/MariaDB. Please see the following pages for more information: Installing Cyber Protection agents in Linux and Protecting MySQL and MariaDB data.


  • You need to migrate a large number of cPanel hosts running on CloudLinux 6.10 or 7.9 to CloudLinux 8.x (e.g. CL8.5)
  • You would like to be able to continue using the same TIBX files and to keep using group plans/multi-machine plans applied to these hosts


Please follow the steps below to migrate:

1. Perquisites:


  1. You make an entire machine backup or disks/volumes backup of a machine with Agent for Linux
  2. Backup fails with the following error:

    No volumes have been found while processing the 'All Volumes' template.


Acronis Cyber Protect Cloud and Acronis Cyber Protect 15 support backing up LDM volumes on all supported operating systems.

Consider the limitations described below when using Acronis Cyber Protect products on machines with LDM volumes such as Windows dynamic disks or Linux LVM.

For Agent-based backup via Agent for Windows/Linux or bootable media:


You have Acronis Backup 12.5 Update 2 (or above) Agent for Linux installed on a Linux machine. You want to update this agent and click Check for updates. You get this error:

No connection to the update server.

In logs, you see many records like:

This article looks at troubleshooting performance problems of the different sub-tasks and operations involved in running a backup plan: backup, replication, validation, recovery etc. 

Performance depends on a lot of factors. For example, it could be hardware limitations that cannot be fixed without changing the hardware or the product under-performing due to conflicts with the system which have to be fixed by Acronis development. So it is important to make sure the performance bottleneck is understood exactly. This article aims to help you do just that. 

The installation of the cyber protection agent fails with the following error message (from installation log):

Error 0x294000d: Socket bind error


  1. You create an entire machine backup of a Linux system where one or more partitions in the system has a label
  2. When you attempt to recover files from the the partition with the label, original location is grayed out during recovery

The installation of the Cyber Protect Agent fails with the following error message in installation log:

Error 0x294000d: Socket bind error


Installing or updating C21.11 or C21.12 agent on CloudLinux7.9 or CloudLinux8.5 (8.x) fails to (re)build snapapi26 and snumbd26 kernel modules. This happens after the latest updates to CloudLinux 7.9 and 8.5 (8.x in general).  trueimage-setup.log contains an error from DKMS about the use of deprecated feature: REMAKE_INITRD in the dkms.conf files of the agent's kernel modules.

Officially supported Linux distributions can be found in User Guide: for Agent, for Management Server. These distributions have been tested in Acronis labs and Acronis products have proven to work appropriately on them.

As a service provider using Acronis Cyber Protect Cloud solution you can have a hybrid storage organized for storing backups (such as Acronis Cyber Infrastructure/Acronis Storage or Acronis Backup Gateway).

There may be a situation requiring to update Backup Storage certificate chain. Below are instructions on how to perform this operation for different versions of Acronis Cyber Infrastructure/Acronis Storage.

Acronis Scheduler is a tool which is responsible for scheduled Acronis operations. If scheduled backups or other activities do not work as configured in backup plan or task, proceed with this article in order to identify the root cause and solve the issue if possible.

Follow these steps to troubleshoot Acronis Scheduler issues:


  • You are trying to install Acronis Agent for Linux
  • Snapapi26 failed to build on the machine and you receive the following error message:
Error! Could not locate dkms.conf file.
File: /var/lib/dkms/snapapi26/0.8.8/source/dkms.conf does not exist.


There are leftovers after previous unsuccessful installation attempts.


This article describes how to programmatically check which Cloud Backup Account the device is registered to and if it's registered at all.

This is useful if you have Acronis Cyber Protect Cloud software installed on the device but is not aware which account it's registered to in Cyber Protection console.

Acronis services to use for upload and download of large amounts of data to cloud

Backing up and restoring large amounts of data to a cloud storage over a slow Internet connection is time-consuming. To help backup service users in these cases, we at Acronis have designed special services for initial upload and download of large amounts of data. These services help end users save time and network traffic by sending the data to the cloud data center on a hard drive or request a hard drive with their backups from the data center.


You would like to change the default port to access the Management Server installed on a Windows or Linux machine. In this article you will find instructions on how to change the ports on both the Management Server and the Agents.


Management Server

On the Windows machine where the Acronis Management Server is installed do the following:

The subject of the E-mail shows the full operation log


  • You are trying to run an Agentless backup of VMs on Scale Computing HC3
  • The backup activity fails on every run and disabling or enabling VSS in the backup plan does not fix the problem


  • You have been trying to install Acronis agent
  • Building the SnapAPI module fails with:

"ERROR: Kernel configuration is invalid.
         include/generated/autoconf.h or include/config/auto.conf are missing.
         Run 'make oldconfig && make prepare' on kernel src to fix it."

Using Wireshark you can collect network tracing logs

Make sure that the antivirus software running in your environment does not block Acronis products. See Acronis Software: Making Acronis Products Compatible with Antivirus Software

Under specific circumstances, the software may crash. It is very important to report a crash instead of trying to workaround it. Normal workflow for a crash problem is the following:

This article lists processes in Acronis Cyber Protect 15 on Linux.