Description

This article describes the issue of ISSU failing, when an upgrade is performed from Junos software that is older than 10.0. Then, the upgrade must be manually completed.

Symptoms

ISSU failure occurs, when an upgrade is performed from Junos software that is older than 10.0. Then, the upgrade must be manually completed.

Solution

This is an occasional issue that arises due to a structural mismatch between the two versions of code.

The issue is resolved in Junos 10.0 and all newer versions of Junos.

If this issue occurs, just proceed with manually completing the upgrade. When the upgrade to Junos 10.0 or later is completed, you can complete the upgrade process via ISSU without interruption. If you still experience issues with ISSU, after upgrading to Junos 10.0 or later, contact JTAC.