Forum Discussion
NimbostratusF5 BIG-IP i11000 stuck at B7 – cannot interrupt boot / ESC not working
Hello everyone,
We are experiencing an issue with an F5 BIG-IP i11000 appliance.
The device powers on, but it does not boot the BIG-IP system. During startup, it stops with a B7 error and does not progress further. We are accessing the unit via the console port, but there is no option to continue the boot process or load the OS.
We have already checked the console connection and baud rate, and we have the official manual available. At this point, it seems to be a low-level boot, BIOS, or hardware-related issue.
Has anyone experienced a similar problem with the iSeries (i11000) platform? Any guidance or troubleshooting steps would be greatly appreciated.
Thank you.
Hi Lucas, hope you're doing well. Regarding the issue that you're facing, I think it's best to open up a support case with F5. At the same time, you can perform some troubleshooting steps before opening a case with us.
According to KB K04158544: Determine possible cause of BIG-IP iSeries platform hardware failures (https://my.f5.com/manage/s/article/K04158544), when the serial console output shows rolling B7 and B9 codes, this indicates a memory failure.
Specific Symptoms for Memory Failure:
- Serial console output: Rolling B7 and B9 codes
- Serial console log: Contains strings with B7 and B9
Example pattern from the KB:
19A1A3A3A3A3A3A3A7A9AAAAABACADAFB0B1AF19A1A3A3A3A3A3A3A7A9AAA7A7A7A7A8A9A9A9A9AAAAAEAFB0B1B4B2B3B6B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B8B9BAB7BF
Additional Context from KB K65073734:
KB K65073734: BIG-IP not booting/responding (https://my.f5.com/manage/s/article/K65073734) specifically addresses your exact symptoms:
- Description: BIG-IP appliance not booting up, console output gets stuck at B7 Hex code after power cycle, no errors on LCD
- Cause: Unknown at time of publication
- Recommended Actions: The unit might need hardware replacement. Open a case with F5 support for confirmation.
Troubleshooting Steps (Before RMA)
Based on similar cases, you should attempt these steps:
- Try accessing the AOM menu:
- Press Esc + Shift + 9 (or Esc + ( on US keyboard)
- If AOM menu appears, try:
- Press "I" to display platform information
- Press "P" to power off/on the host subsystem
- Run hidden diagnostic commands:
- Esc then type "pel" and press Enter
- Esc then type "diag" and press Enter
- Verify console settings:
- Baud rate: 19200
- Try different console cable/laptop to rule out connection issues
- Check if ESC key is working:
- The inability to interrupt boot suggests either console communication issues or severe hardware failure
Recommendation
Based on the evidence from KB articles and similar cases:
This is most likely a hardware failure (memory-related) that will require RMA (Return Merchandise Authorization).
Next Steps:
- If you haven't already, attempt the AOM menu access (Esc + Shift + 9)
- If AOM is accessible, collect the pel and diag logs
- Contact F5 Technical Support to open an RMA case
- Reference KB K04158544 and KB K65073734 when opening your support case
- Provide any console logs you've captured
The hardware failures documented in these KBs typically require replacement. For more information about the RMA process, refer to K12882: Overview of the F5 RMA process (https://my.f5.com/manage/s/article/K12882).
Let us know if the above steps do not work, and we can assist you to open up a case, or you can open the case via myF5.
Cheers,
Mo
1 Reply
- MoFaz
Moderator
Hi Lucas, hope you're doing well. Regarding the issue that you're facing, I think it's best to open up a support case with F5. At the same time, you can perform some troubleshooting steps before opening a case with us.
According to KB K04158544: Determine possible cause of BIG-IP iSeries platform hardware failures (https://my.f5.com/manage/s/article/K04158544), when the serial console output shows rolling B7 and B9 codes, this indicates a memory failure.
Specific Symptoms for Memory Failure:
- Serial console output: Rolling B7 and B9 codes
- Serial console log: Contains strings with B7 and B9
Example pattern from the KB:
19A1A3A3A3A3A3A3A7A9AAAAABACADAFB0B1AF19A1A3A3A3A3A3A3A7A9AAA7A7A7A7A8A9A9A9A9AAAAAEAFB0B1B4B2B3B6B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B7B8B9BAB7BF
Additional Context from KB K65073734:
KB K65073734: BIG-IP not booting/responding (https://my.f5.com/manage/s/article/K65073734) specifically addresses your exact symptoms:
- Description: BIG-IP appliance not booting up, console output gets stuck at B7 Hex code after power cycle, no errors on LCD
- Cause: Unknown at time of publication
- Recommended Actions: The unit might need hardware replacement. Open a case with F5 support for confirmation.
Troubleshooting Steps (Before RMA)
Based on similar cases, you should attempt these steps:
- Try accessing the AOM menu:
- Press Esc + Shift + 9 (or Esc + ( on US keyboard)
- If AOM menu appears, try:
- Press "I" to display platform information
- Press "P" to power off/on the host subsystem
- Run hidden diagnostic commands:
- Esc then type "pel" and press Enter
- Esc then type "diag" and press Enter
- Verify console settings:
- Baud rate: 19200
- Try different console cable/laptop to rule out connection issues
- Check if ESC key is working:
- The inability to interrupt boot suggests either console communication issues or severe hardware failure
Recommendation
Based on the evidence from KB articles and similar cases:
This is most likely a hardware failure (memory-related) that will require RMA (Return Merchandise Authorization).
Next Steps:
- If you haven't already, attempt the AOM menu access (Esc + Shift + 9)
- If AOM is accessible, collect the pel and diag logs
- Contact F5 Technical Support to open an RMA case
- Reference KB K04158544 and KB K65073734 when opening your support case
- Provide any console logs you've captured
The hardware failures documented in these KBs typically require replacement. For more information about the RMA process, refer to K12882: Overview of the F5 RMA process (https://my.f5.com/manage/s/article/K12882).
Let us know if the above steps do not work, and we can assist you to open up a case, or you can open the case via myF5.
Cheers,
Mo
