File and Object Recovery Issues With Linux OS

Product version: 10.7

Last modified: 26 September 2022

Problem

File and/or Object Recovery jobs fail due to iSCSI-related issues on the supported Linux operating systems.

Background

First, make sure that the iscsid service is enabled (as it may be disabled by default) by running the following command:

systemctl enable iscsid.service

Then, reboot the OS or restart the service by running the following:

systemctl restart iscsid.service

Also make sure that open-iscsi is installed by running the following command:

apt-get install open-iscsi -y

You can verify the status of the service with the following command:

systemctl status open-iscsi

The system check should return the following output:

open-iscsi.service - Login to default iSCSI targets
    Loaded: loaded (/lib/systemd/system/open-iscsi.service; enabled; vendor preset: enabled)
     Active: active (exited) since Sat 2020-07-11 07:24:19 UTC; 10s ago
      Docs: man:iscsiadm(8)
             man:iscsid(8)
    Process: 3861 ExecStart=/sbin/iscsiadm -m node --loginall=automatic (code=exited, status=0/SUCCESS)
    Process: 3867 ExecStart=/lib/open-iscsi/activate-storage.sh (code=exited, status=0/SUCCESS)
  Main PID: 3867 (code=exited, status=0/SUCCESS)

If open-iscsi is installed and running, then in most cases, this problem is a result of missing TCP drivers on the respective server. First, check whether this is the case by enter the following commands:

systemctl status iscsi

systemctl status iscsid

lsmod | grep iscsi

If the resulting output is missing the required iscsi_tcp module, then it must be installed to fix recovery issues as it is required for file recovery with NAKIVO Backup & Replication. See an example of correct output below. The output lines confirming that the necessary module is enabled are marked with arrows.

lsmod | grep iscsi
iscsi_tcp 24576 0                    <--
libiscsi_tcp 32768 1 iscsi_tcp              <--
libiscsi 57344 2 libiscsi_tcp,iscsi_tcp
scsi_transport_iscsi 110592 4 libiscsi_tcp,iscsi_tcp,libiscsi

Solution

To install the missing iscsi_tcp module, start by entering the following command in the respective server:

modprobe iscsi_tcp

Double-check that the module is installed by running the lsmod command above. Then, try running the recovery job(s) again. If the job run doesn't encounter the same issue, proceed by adding an entry with the module name ("iscsi_tcp") to /etc/modules-load.d/modules.conf to ensure that the module loads at boot. Reboot the server, re-check if the required modules are present, and retry the original recovery job(s) without the modprobe command.