httpd-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From David Multer <da...@multer.com>
Subject Re: [users@httpd] httpd 2.2.10 mod_proxy bug?
Date Mon, 10 Nov 2008 06:05:51 GMT
More progress:

- I inserted log messages and have determined that APR is getting an  
EAI_AGAIN return value from getaddrinfo() after running for a while.
- I've verified that DNS calls are actually still working in other  
processes via "host subdomain.domain.com", etc.
- Note that I've compiled and run Apache on Mac OS X 10.5.5 (latest).
- My Apache ./configure is as follows. I built and run Apache on the  
same Mac system.
./configure \
--prefix=/usr/local/apache2 \
--enable-mods-shared=all \
--enable-proxy-balancer \
--enable-proxy-ajp \
--enable-proxy-http \
--enable-proxy-ftp \
--enable-proxy-connect \
--enable-proxy \
--enable-ssl \
--with-included-apr \
--enable-dav \
--with-berkeley-db=/usr/local/bdb \
--with-dbm=db4 \
--enable-so
- I'm pretty certain that the failure is due to a memory leak in  
Apache that's causing getaddrinfo() calls to fail. I am continuing to  
look into what could be the source of the leak.
- Memory for the rest of the system looks okay, and the failure seems  
restricted to Apache.
- There is no DNS caching.
- The failure occurs in mod_proxy on the DNS lookup after running a  
browser refresh for a long time.
- I configured the proxy to Tomcat inside a named virtual host. I  
actually have many virtual hosts configured.
- I would recommend a test case that runs continuously to reproduce  
this problem.

Thanks,
David

On Nov 6, 2008, at 8:27 AM, David Multer wrote:

> The problem just started happening again after a day with absolutely  
> no changes of any kind.
>
> On Nov 5, 2008, at 5:46 PM, David Multer wrote:
>
>> I've done some more testing of this problem, and here's some more  
>> detail:
>>
>> - I re-installed 2.2.10 and the problem went away.
>>
>> - I tried switching to mod_proxy_ajp by changing the "http:" prefix  
>> in the ProxyPass and ProxyPassReverse to "ajp:" After restarting  
>> Apache, I started to get the DNS errors again. Reinstalling Apache  
>> (sudo make install) fixed the problem.
>>
>> - Note that the DNS lookup for subdomain.domain.com is only  
>> registered on my internal DNS (BIND9) server. This is because the  
>> subdomains are meant only to be publicized behind my firewall.  
>> Performing a "dig" for subdomain.domain.com works fine. And of  
>> course I can get to Tomcat/Hudson just fine until the problem  
>> happens.
>>
>> - When in the error state, I get this DNS failure regardless of  
>> whether Tomcat is running.
>>
>> - I've never seen this problem before even across many Apache/ 
>> Tomcat config file changes and restarts.
>>
>> - I had initially assumed the problem was introduced by the 2.2.10  
>> change as it's the only difference and I noticed the changelog had  
>> a number of mod_proxy changes.
>>
>> Questions:
>>
>> - Is Apache caching some proxy DNS requests?
>> - I assume the error is purely inside Apache and mod_proxy right?
>> - What could cause this error?
>> - Why would an install clear up the problem?
>>
>> Thanks,
>> David
>>
>> On Nov 4, 2008, at 10:30 PM, David Multer wrote:
>>
>>> I just installed the latest 2.2.10 version of Apache web server  
>>> and noticed it's broken my Tomcat+Hudson setup. I've confirmed  
>>> that falling back to 2.2.9 eliminates the problem. I suppose it  
>>> could be an issue in my config that was only uncovered with the  
>>> latest version, but for now I'll assume it's a real problem.
>>>
>>> My httpd.conf:
>>> ...
>>> LoadModule proxy_module modules/mod_proxy.so
>>> ...
>>> ProxyRequests off
>>> ...
>>> ProxyPass /hudson/ http://subdomain.domain.com:8080/hudson/
>>> ProxyPassReverse /hudson/ http://subdomain.domain.com:8080/hudson/
>>>
>>> Using 2.2.10, when I navigate to http://subdomain.domain.com:8080/hudson/ 
>>>  everything works fine. So Tomcat+Hudson is good. When I go to http://subdomain.domain.com/hudson/

>>>  I get a 502 GET /hudson/ error reporting a DNS failure for  
>>> subdomain.domain.com. Again, both approaches work fine under 2.2.9.
>>>
>>> Here's what shows up in my Apache error log:
>>> [Tue Nov 04 16:04:55 2008] [error] [client X.X.X.X] proxy: DNS  
>>> lookup failure for: subdomain.domain.com returned by /hudson/
>>>
>>> Thanks for any help. I wanted to ask before filing a bug report.
>>>
>>> -David
>>>
>>>
>>> ---------------------------------------------------------------------
>>> The official User-To-User support forum of the Apache HTTP Server  
>>> Project.
>>> See <URL:http://httpd.apache.org/userslist.html> for more info.
>>> To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
>>> "   from the digest: users-digest-unsubscribe@httpd.apache.org
>>> For additional commands, e-mail: users-help@httpd.apache.org
>>>
>>
>>
>> ---------------------------------------------------------------------
>> The official User-To-User support forum of the Apache HTTP Server  
>> Project.
>> See <URL:http://httpd.apache.org/userslist.html> for more info.
>> To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
>> "   from the digest: users-digest-unsubscribe@httpd.apache.org
>> For additional commands, e-mail: users-help@httpd.apache.org
>>
>
>
> ---------------------------------------------------------------------
> The official User-To-User support forum of the Apache HTTP Server  
> Project.
> See <URL:http://httpd.apache.org/userslist.html> for more info.
> To unsubscribe, e-mail: users-unsubscribe@httpd.apache.org
>  "   from the digest: users-digest-unsubscribe@httpd.apache.org
> For additional commands, e-mail: users-help@httpd.apache.org
>


Mime
View raw message