Change the iSCSI timeout

This document (000021037) is provided subject to the disclaimer at the end of this document.

Environment

SUSE Linux Enterprise Server for SAP Applications 15 SP1

Situation

The default timeout for the iSCSI service is 120 sec., if the iSCSI target won't become available during this interval, then iscsid service will give up. Later, you need to manually restart the iscsi service to allow for a new login.

# systemctl restart iscsi.service

Resolution

There are two parameters that determine how long will iscsid attempt to log in before giving up:

node.conn[0].timeo.login_timeout = 15
node.session.initial_login_retry_max = 8

the formula(with default values) is:

   node.conn[0].timeo.login_timeout * node.session.initial_login_retry_max = 120s

Here's an example of how to change the "node.conn[0].timeo.login_timeout" parameter from 15 sec. to 60 sec. Therefore, extend the iSCSI timeout from 2 minutes to 8 minutes.

1.) Get the iqn identifier

# iscsiadm -m session
tcp: [1] 10.10.1.253:3260,1 iqn.2021-12.com.target1:a6898eabcf0acef1273d (non-flash)

2.) Get the current setting

# iscsiadm -m node -T iscsiadm -m node -T iqn.2023-03.com.example:144a7998a41fc9d2a986 --op show | grep login_timeout
node.conn[0].timeo.login_timeout = 15

3.) Set a new value

# iscsiadm -m node -T iqn.2023-03.com.example:144a7998a41fc9d2a986 -o update -n node.conn[0].timeo.login_timeout -v 60

4.) Verify the setting (same as step #2)

# iscsiadm -m node -T iqn.2023-03.com.example:144a7998a41fc9d2a986 --op show | grep login_timeout
node.conn[0].timeo.login_timeout = 60

Note: This is an online task and no need to restart the iscsi service or reboot the system.

Cause

You may need to tune the iSCSI timeout due to your storage or environment setup.
For further information about iSCSI, kindly, check this link https://documentation.suse.com/sles/15-SP1/html/SLES-all/cha-iscsi.html#

Disclaimer

This Support Knowledgebase provides a valuable tool for SUSE customers and parties interested in our products and solutions to acquire information, ideas and learn from one another. Materials are provided for informational, personal or non-commercial use within your organization and are presented "AS IS" WITHOUT WARRANTY OF ANY KIND.