MySQL Bugs: #97365: Server does not start after changing max_allowed

Bug #97365	Server does not start after changing max_allowed_packet parameter
Submitted:	24 Oct 2019 15:25	Modified:	24 Oct 2019 17:05
Reporter:	Rajneesh Gupta	Email Updates:
Status:	Can't repeat	Impact on me:	None
Category:	MySQL Server	Severity:	S2 (Serious)
Version:	8.0.18	OS:	Windows (10)
Assigned to:		CPU Architecture:	x86

Description:
I am running the community server 8.0.18 (from the command line and not the service) and I need to set the max_allowed_packet value to higher than the default. 

However,the server hangs on start with max_allowed_packet=16M, both when
- change is made in the ini file, or
- the value is passed as a command line parameter,

Full logging is on but nothing even gets written to the log. The last entry in the log is:

2019-10-24T14:47:56.916731Z	   10 Connect	root@localhost on  using SSL/TLS
2019-10-24T14:47:56.916973Z	   10 Query	shutdown
2019-10-24T14:47:56.917224Z	   10 Query	

At this point, the only thing possible is to reboot, uninstall and then install again.

How to repeat:
1. Install MySQL with advance logging and turn on all logs and without setting up a service
2. Start server by running mysqld : starts ok
3. Stop server by running mysqladmin -u root -p shutdown : shutsdown ok
4. change the value in the my.ini
5. Start server - server hangs

the conf file with the change in place

Attachment: my.ini (application/octet-stream, text), 17.02 KiB.

Server start

Attachment: 97365.png (image/png, text), 88.42 KiB.

Thank you for the bug report. I couldn't repeat (see screenshot).

Update:

It seemed strange that the server would not start after a legal change - so I just saved the conf (my.ini) file without making any changes. And the got the same result

New max_allowed_packet value

Attachment: 97365_1.png (image/png, text), 75.73 KiB.

server start - attempting shutdown

Attachment: mysqld.png (image/png, text), 38.70 KiB.

Attached screen shot of the server hanging on the console. The process starts - can see it in the windows process list. But does not accept any connections

After new install

Attachment: mysqld.png (image/png, text), 73.18 KiB.

We're sorry, but the bug system is not the appropriate forum for asking help on using MySQL products. Your problem is not the result of a bug.

Just like our Miguel, I attempted this on my local machine and confirmed that no issues while changing option values etc. We checked the screenshot uploaded at [24 Oct 17:10] - looking at the error "mysqld: Can not perform keyring migration : Invalid --keyring-migration-source option. " - it seems to me like you tried to shutdown but using server binary instead of client i.e "mysqld -uroot -p shutdown" <-- this invoked keyring migration mode of MySQL server. You should have used "mysql -uroot -p shutdown".

For details on getting support for MySQL products see http://www.mysql.com/support/
You can also check our forums (free) at http://forums.mysql.com/

Thank you for your interest in MySQL.

This bug report is old but I wanted to comment anyway since it took me a while to find the answer and it may help others. It is an encoding issue with the ini file. See the link below or pasted comment for the explanation and fix. 

I found the ini file from mySQL has 3 invalid ANSI characters. The following line in the file is the culprit "The line # range from 1 to 2^32 − 1. “Unique” means that each ID must be different.". It has 3 Unicode characters. This is causing notepad to append the byte order mark to the text file.

Remove this comment and use Save As in Notepad. Under "Save As" change encoding to ANSI. If you don't remove the comment and then save as ANSI, Notepad will automatically replace the characters with place holders.

https://superuser.com/questions/1421016/mysql-8-0-starts-and-stops-after-my-ini-saved-or-e...