Bug #28977 cannot change the group mysqld runs as
Submitted: 8 Jun 2007 14:35 Modified: 8 Jun 2007 14:46
Reporter: Markus Wernig Email Updates:
Status: Not a Bug Impact on me:
Category:MySQL Server: General Severity:S2 (Serious)
Version:5.0.37, 5.0.22 OS:Any
Assigned to: Magnus Blåudd CPU Architecture:Any

[8 Jun 2007 14:35] Markus Wernig
I've got a Ubuntu Linux 6.06.1 LTS (Intel) installation with mysql-server 5.0.22 (packaged) and a Sun Solaris 9 (Sparc) installation with mysql server 5.0.37 (compiled from source). I need to have mysqld run as a different user from the default one (mysql). So, I configured it in my.cnf:
user = ausername
group = agroupname

But when starting mysqld, I get a rather strange error:
# mysqld
Unknown suffix 'a' used for variable 'group_concat_max_len' (value 'agroupname')
070608 14:04:00 [ERROR] mysqld: Error while setting value 'agroupname' to 'group_concat_max_len'

And, VERY, strangely: The error seems to depend on the first letter of the group name. It does NOT appear if the group name starts with either one of g, k, or m, but with all others. And it occurs before the existence of the group is even checked (i.e. if the first letter is any other than g,k, or m, the error occurs independently of whether the group exists or not).

With g,k,m supposedly representing giga, kilo and mega, this seems to make sense in a way... but why would the value of "group" be used for calculating group_concat_max_len???

Does anybody have an idea what is going on?

thx /markus

How to repeat:
Set the parameter "group" to anything not starting with the letters g,k, or m. mysqld will not start, independently of whether the group exists or not.
[8 Jun 2007 14:46] Magnus Blåudd

MySQL Server(mysqld) has no argument called "group". When you write "group" in the config file or pass it on command line it will be interpreted as if you try to set the argument "group_concat_value" - thus the error message.

To see what parameters the mysqld supports:
$>./mysqld --verbose --help

I guess the manual has some topic about how this works too. ;)

/ Magnus