01-14-2025 07:01 AM
Good day everyone.
Yesterday, I was working on a Cisco ASA 5512-X Firewall that was being used as a VPN Firewall when suddenly I was disconnected from the ASDM. My SSH session from Putty was closed, and I am unable to get back into any of them.
I took a console cable directly connected to the Firewall. I was greeted with the usual log message but with the message "Lua runtime: not enough memory" which kept interrupting my inputs while I was troubleshooting.
when I used the "show memory" command this is what caught my attention
Free memory: 117768378 bytes (7%)
Used memory: 1628998880 bytes (93%)
------------- ------------------
Total memory: 1746767258 bytes (100%)
i assume the high used memory was why my remote sessions were cut off so abruptly and the reason why i can't get back in using ASDM or SSH.
Strangely enough, i was still able to connect and use the VPN without issues, others were still able to connect and use the VPN as well.
I have a feeling i am dealing with the Bug labeled CSCto76775 and i am currently in the process of backing up the running-config and submitting a downtime request form so i can Power-Cycle the device
I have uploaded two text files for reference, one is the "show version" of the device in question and another one is an abbreviated output of the "show memory detail"
My question is, is there another way i can free up the memory so i can re-gain access to the ASDM and re-establish SSH connections or is Power Cycling the only way?
Thank you for your time
Any help would be appreciated.
-Aaron
PS: if this is in the wrong area, please let me know so i can re-ask the question in the correct location.
Solved! Go to Solution.
01-14-2025 09:29 AM
- FYI : https://bst.cloudapps.cisco.com/bugsearch/bug/CSCta09265
https://bst.cloudapps.cisco.com/bugsearch/bug/CSCto76775
M.
01-14-2025 07:36 AM
I will check it
Thanks for waiting
MHM
01-14-2025 07:46 AM
Show proc cpu-hog
Show proc mem
Show mem detail
Show perfmon
Share above
Thanks
MHM
01-14-2025 09:48 AM
01-14-2025 09:29 AM
- FYI : https://bst.cloudapps.cisco.com/bugsearch/bug/CSCta09265
https://bst.cloudapps.cisco.com/bugsearch/bug/CSCto76775
M.
01-14-2025 09:52 AM
Thank you for the links to those bug reports M.
I do see that alot of my device's symptoms seem to corallite with the bug reports.
it looks like the only solution, as far as i could see, is to power-cycle the firewall in question.
What i don't understand is with such a high memory load everything is running properly the Firewall and the VPN. i would assume that i would start to see slowdowns or reports of slow and or failing connections to the VPN.
is there something im missing or not understanding?
01-14-2025 10:35 AM
Quick update
I am unable to backup the running-config to USB or TFTP i keep getting the error "No Memory"
i assume it has to do with the high memory usage.
01-14-2025 11:11 AM
- Can you still show it with show running-config ?
In that case you could for instance connect with PuTTY and enable logging of the session.
The above command can then be used to have the output of the running configuration , being preserved
in the PuTTY logfile too (e.g.)
M.
01-14-2025 12:25 PM
I did not think to do it that way, thank you for the suggestion.
My only issue is the repeating "Lua runtime: not enough memory" that will be happening but that can be easily edited out.
For extra peace of mind, are there any commands you can think of that I should run to make sure that once i power-cycle the device it will come back up.
i don't plan on removing any power supplies, once i get the approval for the window of time i will just connect via console cable and just do the reload command.
01-15-2025 01:46 AM
@aaron-rousch wrote : >....For extra peace of mind, are there any commands you can think of that I should run to make sure that once i power-cycle the device it will come back up.
Not that I know off , usually when there is a problem concerning resources it comes down to 'just power-cycle or reboot' ; the earlier method I mentioned was kind of an emergency saver for the running configuration if needed.
- Often useful on ASA platforms is the https://software.cisco.com/download/home/286311499/type/286312309/os
CLI Analyzer (needs to be downloaded first). It can run diagnostics on the ASA , see buttons at the top.
M.
01-15-2025 06:49 AM
Thank you for the CLI Analyzer, i have downloaded it and will start looking at the documentation for it.
I have one more question, for you Sir. do you know of a way to suppress the "Lua runtime: not enough memory" messages so that i can get an uninterrupted output of the show running-config?
Thank you again
01-15-2025 07:10 AM
- No , not if the device is in that current state ; your (only) options are to reboot and check if that can help and also look
at the most recent (advisory) software version for your particular model. Upgrading becomes advised especially
if you are currently using an older release ,
M.
01-15-2025 07:18 AM
Understood.
Thank you for all the help, i am currently in the process of hopefully getting a Cisco support contract with the company i work for.
01-15-2025 07:59 AM
You share output yesterday' give me some time to check it.
MHM
01-15-2025 08:02 AM
Okay, thank you MHM i will remove the "Accept as Solution" and keep the thread open untill i hear back from you.
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