Connect to the Karaf console:
Increase the log level, helps understanding if the upgrade process is working
openhab> log:set debug com.zsmartsystems.zigbee.app.otaserver.ZclOtaUpgradeServer
Download the right firmware and save it in /var/lib/openhab2/
Get a list of your zigbee devices, and identify which one you want to update
openhab> zigbee nodes
Network Addr IEEE Address Logical Type State EP Profile Device Type Manufacturer Model
0 0000 00124B0009EF006A COORDINATOR UNKNOWN
21583 544F 841826000000ECE1 ROUTER UNKNOWN 3 ZIGBEE_LIGHT_LINK POINT_OF_SALE OSRAM Classic A60 TW
45231 B0AF 841826000000EC95 ROUTER UNKNOWN 3 ZIGBEE_LIGHT_LINK POINT_OF_SALE OSRAM Classic A60 TW
48139 BC0B 841826000000EEBD ROUTER UNKNOWN 3 ZIGBEE_LIGHT_LINK POINT_OF_SALE OSRAM Classic A60 TW
50188 C40C 841826000001687F ROUTER UNKNOWN 3 ZIGBEE_LIGHT_LINK POINT_OF_SALE OSRAM PAR16 50 TW
57754 E19A 8418260000CA12E2 ROUTER UNKNOWN 3 ZIGBEE_LIGHT_LINK 0210 OSRAM Classic A60 RGBW
Start the update with
openhab> zigbee otaupgrade start [Network Address]/[Endpoint] [filename.ota]
# EXAMPLE
# openhab> zigbee otaupgrade start 45231/3 ZLL_MK_0x01020509_CLA60_TW.ota
Check the logs
openhab> log:tail
2020-02-21 20:30:39.136 [DEBUG] [ee.app.otaserver.ZclOtaUpgradeServer] - B0AF/3 OTA status updated to OTA_WAITING.
2020-02-21 20:30:39.502 [DEBUG] [ee.app.otaserver.ZclOtaUpgradeServer] - B0AF/3 OTA status updated to OTA_TRANSFER_IN_PROGRESS.
2020-02-21 20:30:40.366 [DEBUG] [ee.app.otaserver.ZclOtaUpgradeServer] - B0AF/3 OTA Data: Sending 60 bytes at offset 0
2020-02-21 20:30:40.873 [DEBUG] [ee.app.otaserver.ZclOtaUpgradeServer] - B0AF/3 OTA Data: Sending 60 bytes at offset 60
2020-02-21 20:30:40.975 [DEBUG] [ee.app.otaserver.ZclOtaUpgradeServer] - B0AF/3 OTA Data: Sending 60 bytes at offset 120
[snip]
2020-02-21 20:38:27.498 [DEBUG] [ee.app.otaserver.ZclOtaUpgradeServer] - B0AF/3 OTA Data: Sending 60 bytes at offset 133320
2020-02-21 20:38:27.603 [DEBUG] [ee.app.otaserver.ZclOtaUpgradeServer] - B0AF/3 OTA Data: Sending 60 bytes at offset 133380
2020-02-21 20:38:27.691 [DEBUG] [ee.app.otaserver.ZclOtaUpgradeServer] - B0AF/3 OTA Data: Sending 4 bytes at offset 133440
2020-02-21 20:38:28.076 [DEBUG] [ee.app.otaserver.ZclOtaUpgradeServer] - B0AF/3 OTA status updated to OTA_TRANSFER_COMPLETE.
2020-02-21 20:38:28.416 [DEBUG] [ee.app.otaserver.ZclOtaUpgradeServer] - B0AF/3 OTA status updated to OTA_UPGRADE_FIRMWARE_RESTARTING.
2020-02-21 20:38:51.236 [DEBUG] [ee.app.otaserver.ZclOtaUpgradeServer] - B0AF/3 OTA status updated to OTA_UPGRADE_COMPLETE.
Restore the original log level
openhab> log:set info com.zsmartsystems.zigbee.app.otaserver.ZclOtaUpgradeServer
Keep in mind that with the current Openhab version (2.5.2) and CC2531, the update process is not working reliably. The next release should include a fix.