# Mongrel .pids disappearing?

**URL:** <https://www.ruby-forum.com/t/mongrel-pids-disappearing/147657>\
**Category:** Mongrel\
**Created:** [September 4, 2008, 1:24am UTC](https://www.ruby-forum.com/t/mongrel-pids-disappearing/147657 "2008-09-04T01:24:26Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![Christopher\_Opena](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/e68b1a/32.png) [@Christopher\_Opena](https://www.ruby-forum.com/u/Christopher_Opena)\
**Post date:** [September 4, 2008, 1:24am UTC](https://www.ruby-forum.com/t/mongrel-pids-disappearing/147657/1 "2008-09-04T01:24:26Z")

</div>

Hello everyone, new to the list 🙂

Strange problem with Mongrels that we’re having in a few cases…the  
Mongrels start up fine, but as part of a long Capistrano deploy +  
database  
we will normally cycle them - normally no issues there. In those edge  
cases, we’ve seen that the mongrel .pids have just up and disappeared  
while  
running, so when shutting them down we get the error message that the  
.pids  
do not exist. Normally not a problem, except that when restarting them  
(and  
thereby needing to create a new pid), the log comes back with the error  
message:

\*\* Daemonized, any open files are closed. Look at log/mongrel.4102.pid  
and log/mongrel.4102.log for info.  
\*\* Starting Mongrel listening at 127.0.0.1:4102  
[http://127.0.0.1:9002/](http://127.0.0.1:9002/)  
/usr/lib64/ruby/gems/1.8/gems/mongrel-1.0.1/lib/mongrel/tcphack.rb:12:in  
`initialize\_without\_backlog’: Address already in use - bind(2)  
(Errno::EADDRINUSE)

Logging into the server over ssh and executing ‘sudo /usr/sbin/lsof  
-i:4102’  
reveals that indeed a mongrel process is running without a .pid. From  
what  
I can see there is no log rotation, cron job, or similar activity on the  
box  
that would be deleting the pids. In fact, some of the 6 .pids are there  
while others are not. The pattern also changes with regard to which  
ones  
are missing, which is mildly aggravating.

Box is CentOS 5.1 if that helps. I also noted that someone was having  
this  
issue before and was cured by running the MySQL gem after seeing MySQL  
connections going stale / dying on their server, but we’re already  
running  
the MySQL gem and are not seeing those errors in the Mongrel log.

In fact, looking at the last successful start just before the error  
shown  
above, there are no other errors. In other words, Mongrel starts up  
daemonized without an issue or any errors in the log, and then some time  
later (in this case, 2 weeks), trying to stop them generates a  
nonexistent  
.pid error. The subsequent start attempt generates the ‘Address already  
in  
use’ message, which forces us to log in and actually kill the processes  
before we can start up again.

Processes without .pids don’t seem to be using more or less memory than  
usual.

We are stopping and starting the mongrels with the following bash  
script:

mongrel\_rails cluster::start -C $MONGREL\_CONF  
mongrel\_rails cluster::stop -C $MONGREL\_CONF

Mongrel version is 1.0.1 (as described above), and MySQL gem is 2.7.

Has anyone seen a similar issue, and if so did you figure out the root  
cause? I’m a bit at a loss with the mongrel logs not giving any  
information  
nor the system giving any inidication that it deleted the .pid files.  
Any  
help is greatly appreciated.

-Chris.

---

<div class="post-metadata">

**Author:** ![Christopher\_Opena](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/e68b1a/32.png) [@Christopher\_Opena](https://www.ruby-forum.com/u/Christopher_Opena)\
**Post date:** [September 4, 2008, 2:18am UTC](https://www.ruby-forum.com/t/mongrel-pids-disappearing/147657/2 "2008-09-04T02:18:16Z")

</div>

I’ve been experiencing this exact same problem for months. Still  
haven’t figured out what the cause is.

I’m on solaris 10 x86

-Steven

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<div class="post-metadata">

**Author:** ![Christopher\_Opena](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/e68b1a/32.png) [@Christopher\_Opena](https://www.ruby-forum.com/u/Christopher_Opena)\
**Post date:** [April 14, 2009, 7:23pm UTC](https://www.ruby-forum.com/t/mongrel-pids-disappearing/147657/3 "2009-04-14T19:23:55Z")

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Hi, did you ever find what was causing this? I have the same issue on  
CentOs.

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<div class="post-metadata">

**Author:** ![Christopher\_Opena](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/e68b1a/32.png) [@Christopher\_Opena](https://www.ruby-forum.com/u/Christopher_Opena)\
**Post date:** [October 26, 2009, 11:14pm UTC](https://www.ruby-forum.com/t/mongrel-pids-disappearing/147657/4 "2009-10-26T23:14:39Z")

</div>

I spent so much time on this pid sh… googling for hours. Hope I can  
help others! Seems like running as a daemon solves the problem. just add  
-d at the end and it decides to create the pid file. I’m sorry if this  
isn’t the problem/solution you guys are having.

mongrel\_rails start -d

It really tricked me with its output on mongrel\_rails.

\*\* Starting Mongrel listening at 0.0.0.0:3000  
\*\* Starting Rails with development environment…  
\*\* Rails loaded.  
\*\* Loading any Rails specific GemPlugins  
\*\* Signals ready. TERM =\> stop. USR2 =\> restart. INT =\> stop (no  
restart).  
\*\* Rails signals registered. HUP =\> reload (without restart). It might  
not work well.  
\*\* Mongrel 1.1.5 available at 0.0.0.0:3000

Of, course, neither restart nor stop worked, so I tried sending that  
USR2 signal manually, finding it’s pid with ps, then

kill -USR2 20316

Back in the first term window I saw this:

- USR2 signal received.  
\*\* Restarting with arguments: ruby  
/Library/Ruby/Gems/1.8/gems/mongrel-1.1.5/bin/mongrel\_rails start  
Can’t restart unless in daemon mode.

OK, trying the obvious worked. You can see the pid file is there in the  
log directory. Or am I totally off here??

---

<div class="post-metadata">

**Author:** ![Christopher\_Opena](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/e68b1a/32.png) [@Christopher\_Opena](https://www.ruby-forum.com/u/Christopher_Opena)\
**Post date:** [April 14, 2009, 8:02pm UTC](https://www.ruby-forum.com/t/mongrel-pids-disappearing/147657/5 "2009-04-14T20:02:21Z")

</div>

I reinstalled RoR and mongrel on my Sun Solaris box and the problem  
disappeared.

Kevin

---

<div class="post-metadata">

**Author:** ![Christopher\_Opena](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/e68b1a/32.png) [@Christopher\_Opena](https://www.ruby-forum.com/u/Christopher_Opena)\
**Post date:** [November 2, 2009, 7:44pm UTC](https://www.ruby-forum.com/t/mongrel-pids-disappearing/147657/6 "2009-11-02T19:44:52Z")

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Is there a version of mongrel out yet that has a --prefix that works  
with latest versions of Rails?

When I do a “gem install mongrel”, I get mongrel 1.1.5.

Using Rails 2.3.4, if I try launching mongrel with “–prefix  
/something”, I get an error about:

uninitialized constant ActionController::AbstractRequest

As this problem was first reported a year ago, I’m hoping there’s a  
version of mongrel that handles it, that I just haven’t managed to  
actually install with a naive “gem install mongrel”, it’s hiding  
somewhere else?

Or is this really not fixed in a mongrel release yet?

Any advice welcome. (I know how to set the prefix in environment.rb  
_instead of_ mongrel command line; but I really want to do it in the  
mongrel command line sometimes).

Jonathan