To all who thank you.
For some reason, propobably operator error found that all of the permissions
on the /var/qmail directory were owned by alias. I fixed the file
permissions and boom. Its alive!!!!!! They said it couldn't be done but
its alive!!!!
:)
Thanks again to all who helped
Brian
-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, June 20, 2000 9:41 AM
To: [EMAIL PROTECTED]
Subject: RE: Need Help restarting qmail
Brian-
Here's an overview of Mutex's. Skip to the last paragraph if you don't care
about the theory and just want to know what I know specifically about
qmail's mutex (which I'll warn you in advance isn't much).
Ok, here's as much as I know right now from my studying of Comp
Sci...mutex's (MUTually EXclusive) are generally "lock" mechanisms. They
ensure that operations are atomic, ie, that they'll be run completely and/or
one at a time before something else can take control. Here's an example:
You have a file blah.txt that looks like this:
user1
user2
user3
This is a list of available usernames to assign to people. When an admin on
your network wants to create a user, they remove the user from that list,
create the user, and save the list. You have two administrators who want to
create users. Admin1 opens blah.txt. Admin1 needs to create one user, so
he deletes user1 from the list, but he DOES NOT save the file yet, becuase
he's not supposed to until he finishes creating the user.(I know this is
illogical, but suspend disbelief for the example). Now,to Admin1, the file
blah.txt now looks like:
user2
user3
While Admin1's creating the user, Admin2, also needing to create a user,
opens up file blah.txt. Becuase Admin1 has yet to save, Admin2 sees blah.txt
as:
user1
user2
user3
He then also deletes user1 from the list, and goes to create a user. They
both finish creating, and both save the file. Now, they've both created a
user user1. This does't work well.
So, how does one fix this? Well, you can create a script, called checklock.
This file runs whenever an attempt to open blah.txt occurs. It checks to
see if a file, called "lock" is present. If not, it allows the user to open
the file, and creates the file "lock". If the file is present, it lets the
user know "sorry, someone's got this file open. Please try again later".
Now, only one person can open the file at a time.
That's a somewhat oversimplified, not entirely accurate idea of what a mutex
is, but you get the idea. Now, as far as qmail goes, the mutex is the file
/var/qmail/queue/lock/sendmutex. I think qmail uses this to make sure it
doesn't start multiple instances of itself. As for why it won't open, I'm
afraid I can't help there. Perhaps re-compiling would help, if the
sendmutex file has somehow gotten corrupted? I don't exactly know, but you
may be able to play around with the system or again just re-compile. Anyone
else have more info on this?
Hope that gives a glimmer of hope, sorry I couldn't be more helpful...
-Brian
-----Original Message-----
From: Hand, Brian C. [mailto:[EMAIL PROTECTED]]
Sent: Monday, June 19, 2000 4:54 PM
To: '[EMAIL PROTECTED]'
Subject: RE: Need Help restarting qmail
Anyone out there can they please let me know what the problem is. I need to
get this server back up soon.
Please Help
*Cries of Despiration*
Thanks
Brian
-----Original Message-----
From: Hand, Brian C. [mailto:[EMAIL PROTECTED]]
Sent: Monday, June 19, 2000 1:25 PM
To: '[EMAIL PROTECTED]'
Subject: Need Help restarting qmail
> All,
>
> I am getting the following error. It is preventing qmail from starting.
> This is a clip from syslog.
>
> Jun 19 13:07:13 listserv qmail: [ID 748625 mail.alert] 961438033.590877
> alert: cannot start: unable to open mutex
>
> What is the mutex and what do I do to get qmail started?
>
> Thanks
> Brian
