In-Service Software Upgrade (ISSU)

Information About In-Service Software Upgrade (ISSU)

ISSU is a process that upgrades an image to another image on a device while the network continues to forward packets. ISSU helps network administrators avoid a network outage when performing a software upgrade. ISSU is supported in install mode.

ISSU is supported in dual SUP HA and StackWise Virtual system. In-Service Software Upgrade is performed either in a single step or in three-steps.

ISSU Support between Releases

Supported Scenarios

Unsupported Scenarios

  • Within a major release train (16.x or 17.x or 18.x ), ISSU is supported between any two EMs that are released not more than 3 years apart.

  • Within a major release train, ISSU is supported from:

    • Any EM (EM1, EM2, EM3) to another EM (EM1, EM2, EM3)

      Example: 16.9.x to 16.12.x, 17.3.x to 17.6.x, 17.6.x to 17.9.x

    • Any release within the same EM

      Example: 16.9.2 to 16.9.3 or 16.9.4 or 16.9.x, 16.12.1 to 16.12.2 or 16.12.3 or 16.12.x, 17.3.1 to 17.3.2 or 17.3.3 or 17.3.x

  • Switching ISSU Recommendation:

    • From any EM recommended release on CCO to current EM Recommended release on CCO

Note 

FPGA upgrade has been decoupled from ISSU to facilitate ISSU within the major release train for 3 years. You can upgrade FPGA through CLI during maintenance windows that require full reload.

  • Between major release trains, ISSU is not supported from:

    • An EM of a major release train to an EM of another major release train

      Example: 16.x.x to 17.x.x or 17.x.x to 18.x.x is not supported

    • An SM to EM or EM to SM

      Example: 16.10.x or 16.11.x to 16.12.x is not supported

  • ISSU is not supported on engineering special releases and .s (or similar) images.

  • ISSU is not supported between Licensed Data Payload Encryption (LDPE) and No Payload Encryption (NPE) Cisco IOS XE software images.

  • ISSU downgrades are not supported.

Note 

No configuration changes should be performed while ISSU is being performed.

Supported Platforms and Recommended Releases for ISSU

Platforms

ISSU Starting Release

ISSU Recommended Starting Release

C3850-XS (SVL)

16.9.2

16.9.3

C9400 (4,7,10 slots-dual supervisor single chassis)

16.9.1

16.9.3

C9400 (SVL 10-slot)

16.12.1c

16.12.2

C9400 (SVL 4,7 slots)

16.9.2

16.9.3

C9500 (SVL)

16.9.2

16.9.3

C9500 High Performance (SVL)

16.12.1c

16.12.2

C9600 (dual supervisor)

16.12.1

16.12.2

C9600 (SVL)

16.12.1

16.12.2

Release Support Matrix

The following tables show ISSU support between EMs.

  • For Catalyst 3850, Catalyst 9400, Catalyst 9500 with StackWise Virtual, ISSU support starts from Cisco IOS XE Fuji 16.9.2.

  • For Catalyst 9400 in dual supervisor module configuration, ISSU support starts from Cisco IOS XE Fuji 16.9.1.


    Note

    All upgrades from 16.9.x up to 16.9.5 in the 16.9 release train, and up to 16.12.2 in the 16.12 release train, require installation of Software Maintenance Upgrade (SMU) packages. Upgrades from 16.9.5 and 16.12.2 to later releases do not require installation of SMU packages.
  • For Catalyst 9500 High Performance, ISSU support starts from Cisco IOS XE Gibraltar 16.12.1c.

  • For Catalyst 9600 in dual supervisor module configuration and with StackWise Virtual, ISSU support starts from Cisco IOS XE Gibraltar 16.12.1.

Catalyst 3850 with StackWise Virtual

From/To

16.9.2

16.9.3a

16.9.4

16.9.5

16.12.1

16.12.3

16.12.3a

16.12.4

16.12.5

16.12.5b

16.9.2

16.9.3a

x

16.9.4

x

x

16.9.5

x

x

x

16.12.1

x

x

x

x

16.12.3

x

x

x

x

x

16.12.3a

x

x

x

x

x

x

16.12.4

x

x

x

x

x

x

x

16.12.5

x

x

x

x

x

x

x

x

16.12.5b

x

x

x

x

x

x

x

x

x

Catalyst 9400 with Dual Supervisor Module Configuration

From/To

16.9.1

16.9.2

16.9.3

16.9.4

16.9.5

16.12.1c

16.12.2

16.12.3

16.12.3a

16.12.4

16.12.5

16.12.5b

17.3.1

17.3.2a

17.3.3

17.3.4

17.6.1

16.9.1*

x

x

x

x

x

16.9.2*

x

x

x

x

x

x

16.9.3*

x

x

x

x

x

x

x

16.9.4*

x

x

x

x

x

x

x

x

16.9.5

x

x

x

x

x

x

x

x

x

16.12.1c*

x

x

x

x

x

x

x

x

x

x

16.12.2

x

x

x

x

x

x

x

x

x

x

x

16.12.3

x

x

x

x

x

x

x

x

x

x

x

x

16.12.3a

x

x

x

x

x

x

x

x

x

x

x

x

x

16.12.4

x

x

x

x

x

x

x

x

x

x

x

x

x

x

16.12.5

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

16.12.5b

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

17.3.1

x

x

x

x

x

x

x

x

x

x

x

x

17.3.2a

x

x

x

x

x

x

x

x

x

x

x

x

x

17.3.3

x

x

x

x

x

x

x

x

x

x

x

x

x

x

17.3.4

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

17.6.1

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

*Requires SMU installation before performing ISSU. See Release Notes for Cisco Catalyst 9400 Series Switches, Cisco IOS XE Fuji 16.9.x for upgrades in the 16.9.x train and Release Notes for Cisco Catalyst 9400 Series Switches, Cisco IOS XE Gibraltar 16.12.x for upgrades in the 16.12.x train, for detailed steps.

Catalyst 9400 with StackWise Virtual

From/To

16.9.2

16.9.3*

16.9.4

16.9.5

16.12.1c

16.12.2

16.12.3

16.12.3a

16.12.4

16.12.5

16.12.5b

17.3.1

17.3.2a

17.3.3

17.3.4

17.6.1

16.9.2*

x

x

x

x

x

16.9.3

x

x

x

x

x

x

16.9.4

x

x

x

x

x

x

x

16.9.5

x

x

x

x

x

x

x

x

16.12.1c

x

x

x

x

x

x

x

x

x

16.12.2

x

x

x

x

x

x

x

x

x

x

16.12.3

x

x

x

x

x

x

x

x

x

x

x

16.12.3a

x

x

x

x

x

x

x

x

x

x

x

x

16.12.4

x

x

x

x

x

x

x

x

x

x

x

x

x

16.12.5

x

x

x

x

x

x

x

x

x

x

x

x

x

x

16.12.5b

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

17.3.1

x

x

x

x

x

x

x

x

x

x

x

17.3.2a

x

x

x

x

x

x

x

x

x

x

x

x

17.3.3

x

x

x

x

x

x

x

x

x

x

x

x

x

17.3.4

x

x

x

x

x

x

x

x

x

x

x

x

x

x

17.6.1

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

*Requires SMU installation before performing ISSU from 16.9.2 to 16.9.3. See Release Notes for Cisco Catalyst 9400 Series Switches, Cisco IOS XE Fuji 16.9.x for upgrades in the 16.9.x train.

Catalyst 9500 with StackWise Virtual

From/To

16.9.2

16.9.3*

16.9.4

16.9.5

16.12.1

16.12.2

16.12.3

16.12.3a

16.12.4

16.12.5

16.12.5b

17.3.1

17.3.2a

17.3.3

17.3.4

17.6.1

16.9.2*

x

x

x

x

x

16.9.3

x

x

x

x

x

x

16.9.4

x

x

x

x

x

x

x

16.9.5

x

x

x

x

x

x

x

x

16.12.1

x

x

x

x

x

x

x

x

x

16.12.2

x

x

x

x

x

x

x

x

x

x

16.12.3

x

x

x

x

x

x

x

x

x

x

x

16.12.3a

x

x

x

x

x

x

x

x

x

x

x

x

16.12.4

x

x

x

x

x

x

x

x

x

x

x

x

x

16.12.5

x

x

x

x

x

x

x

x

x

x

x

x

x

x

16.12.5b

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

17.3.1

x

x

x

x

x

x

x

x

x

x

x

17.3.2a

x

x

x

x

x

x

x

x

x

x

x

x

17.3.3

x

x

x

x

x

x

x

x

x

x

x

x

x

17.3.4

x

x

x

x

x

x

x

x

x

x

x

x

x

x

17.6.1

x

x

x

x

x

x

x

x

x

x

x

x

x

x

x

*Requires SMU installation before performing ISSU from 16.9.2 to 16.9.3. See Release Notes for Cisco Catalyst 9500 Series Switches, Cisco IOS XE Fuji 16.9.x for upgrades in the 16.9.x train.

Catalyst 9500 High Performance with StackWise Virtual

From/To

16.12.1c

16.12.2

16.12.3

16.12.3a

16.12.4

16.12.5

16.12.5b

17.3.1

17.3.2a

17.3.3

17.3.4

17.6.1

16.12.1.c

x

x

x

x

x

16.12.2

x

x

x

x

x

x

16.12.3

x

x

x

x

x

x

x

16.12.3a

x

x

x

x

x

x

x

x

16.12.4

x

x

x

x

x

x

x

x

x

16.12.5

x

x

x

x

x

x

x

x

x

x

16.12.5b

x

x

x

x

x

x

x

x

x

x

x

17.3.1

x

x

x

x

x

x

x

17.3.2a

x

x

x

x

x

x

x

x

17.3.3

x

x

x

x

x

x

x

x

x

17.3.4

x

x

x

x

x

x

x

x

x

x

17.6.1

x

x

x

x

x

x

x

x

x

x

x

Catalyst 9600 in Dual Supervisor Module Configuration and with StackWise Virtual

From/To

16.12.1

16.12.2

16.12.3

16.12.3a

16.12.4

16.12.5

16.12.5b

17.3.1

17.3.2a

17.3.3

17.3.4

17.6.1

16.12.1

x

x

x

x

x

16.12.2

x

x

x

x

x

x

16.12.3

x

x

x

x

x

x

x

16.12.3a

x

x

x

x

x

x

x

x

16.12.4

x

x

x

x

x

x

x

x

x

16.12.5

x

x

x

x

x

x

x

x

x

x

16.12.5b

x

x

x

x

x

x

x

x

x

x

x

17.3.1

x

x

x

x

x

x

x

17.3.2a

x

x

x

x

x

x

x

x

17.3.3

x

x

x

x

x

x

x

x

x

17.3.4

x

x

x

x

x

x

x

x

x

x

17.6.1

x

x

x

x

x

x

x

x

x

x

x

Additional References for ISSU