ANDU paused due to hung or long running BIOS upgrade

Applies to

• ONTAP 9
• FAS/AFF A-Series/AFF C-Series/ASA
• Automated non-disruptive upgrade (ANDU)
• BIOS Update

Issue

• Post ONTAP upgrade when controller boots, the bios gets upgraded and stops as below

SP/BMC system log:

New BIOS version: 18.15
New LOADER version: 8.6.1
Enabling write access to the flash ME region...
ME region - write access enabled.
Saving Primary Image to Backup flash device
--------.+...------------.+.+.+.+.+.+.+ done. 33554432 bytes written
Updating Primary Boot Flash
--------.+....-----------------------.+.+ done. 33554432 bytes written

Firmware update complete.  System rebooting...

SP/BMC events all:

Record 971: Fri Mar 27 01:15:44.086283 2026 [IPMI.notice]: 02d5 | 02 | EVT: 6fc220ff | System_FW_Status | Assertion Event, "Bootloader is running"
Record 972: Fri Mar 27 01:16:40.141367 2026 [IPMI.notice]: 02d6 | 02 | EVT: 6fc222ff | System_FW_Status | Assertion Event, "Bootloader is programming the secondary flash"
Record 973: Fri Mar 27 01:19:16.000000 2026 [SysFW.notice]: Done archiving flash on primary to the backup.
Record 974: Fri Mar 27 01:19:16.000000 2026 [SysFW.notice]: Updating flash. Current BIOS version: 18.14
Record 975: Fri Mar 27 01:19:16.000000 2026 [SysFW.notice]: New BIOS version: 18.15
Record 976: Fri Mar 27 01:19:22.309330 2026 [IPMI.notice]: 02d7 | 02 | EVT: 6fc221ff | System_FW_Status | Assertion Event, "Bootloader is programming the primary flash"
Record 977: Fri Mar 27 01:21:44.000000 2026 [SysFW.notice]: Done updating flash on the primary.
Record 978: Fri Mar 27 01:21:44.000000 2026 [SysFW.notice]: Flash updating process complete.

• EMS shows Ontap Upgrade is paused as below:

[node01-01: notifyd: callhome.andu.pausederr:alert]: params: {'epoch': '#######-####-####-####-############', 'subject': 'AUTOMATED NDU PAUSED'}

• The node may also exhibit the symptom where the SP/BMC is unresponsive and not reachable via its configured IP address.