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Home Documentation Junos OS Release Notes: Junos OS Release 21.4R3 Junos OS Release Notes for EX Series

Release Notes: Junos OS Release 21.4R3

Junos OS Junos OS Evolved
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Release Notes: Junos OS Release 21.4R3
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{ "lLangCode": "en", "lName": "English", "lCountryCode": "us", "transcode": "en_US" }
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Migration, Upgrade, and Downgrade Instructions

date_range 29-Aug-22
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This section contains the upgrade and downgrade support policy for Junos OS for EX Series switches. Upgrading or downgrading Junos OS might take several minutes, depending on the size and configuration of the network.

Starting in Junos OS release 21.4R3, all Junos OS products which were previously running on FreeBSD 11.x based Junos OS are migrated to FreeBSD 12.x based Junos OS except EX4400. EX4400 still runs on FreeBSD 11.x based Junos OS.

For information about software installation and upgrade, see the Installation and Upgrade Guide.

Upgrade and Downgrade Support Policy for Junos OS Releases and Extended End-Of-Life Releases

We have two types of releases, standard EOL and EEOL:

  • Standard End of Life (EOL) releases have engineering support for twenty four months after the first general availability date and customer support for an additional six more months.

  • Extended End of Life (EEOL) releases have engineering support for thirty six months after the first general availability date and customer support for an additional six more months.

For both standard EOL and EEOL releases, you can upgrade to the next three subsequent releases or downgrade to the previous three releases. For example, you can upgrade from 20.4 to the next three releases – 21.1, 21.2 and 21.3 or downgrade to the previous three releases – 20.3, 20.2 and 20.1.

For EEOL releases only, you have an additional option - you can upgrade directly from one EEOL release to the next two subsequent EEOL releases, even if the target release is beyond the next three releases. Likewise, you can downgrade directly from one EEOL release to the previous two EEOL releases, even if the target release is beyond the previous three releases. For example, 20.4 is an EEOL release. Hence, you can upgrade from 20.4 to the next two EEOL releases – 21.2 and 21.4 or downgrade to the previous two EEOL releases – 20.2 and 19.4.

Table 1: EOL and EEOL Releases
Release Type End of Engineering (EOE) End of Support (EOS) Upgrade/Downgrade to subsequent 3 releases Upgrade/Downgrade to subsequent 2 EEOL releases
Standard End of Life (EOL) 24 months End of Engineering + 6 months Yes No
Extended End of Life (EEOL) 36 months End of Engineering + 6 months Yes Yes

For more information about standard EOL and EEOL releases, see https://www.juniper.net/support/eol/junos.html.

For information about software installation and upgrade, see the Installation and Upgrade Guide.

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