# Error\_log levels **URL:** \ **Category:** NGINX\ **Created:** [April 9, 2010, 4:18am UTC](https://www.ruby-forum.com/t/error-log-levels/186578 "2010-04-09T04:18:34Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![flash](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/f/f475e1/32.png) [@flash](https://www.ruby-forum.com/u/flash)\ **Post date:** [April 9, 2010, 4:18am UTC](https://www.ruby-forum.com/t/error-log-levels/186578/1 "2010-04-09T04:18:34Z")
I’m getting a lot of entries in my error\_log from memcache throwing a 404 and sending the request to the back end. 2010/04/08 21:07:50 29914#0: \*3207 pcre\_exec() failed: -8 on “[example.com](http://example.com)” using “” while sending to client, client: 66.249.71.23, server: \_, request: “GET [example.com](http://example.com) HTTP/1.1”, upstream: “memcached://127.0.0.1:11211”, host: “[example.com](http://example.com)” I’m assuming this is correct behavior since it cannot find the requested url in memory; however, I have not been able to find any error level descriptions in the docs - could you either fill me in on what level I need to include on my conf file or point me in the direction of where this info can be found? I’m looking to remove the “alert” log events to try and clean up my error\_log a bit. Thank you Flash Posted at Nginx Forum: > **[error\_log levels](https://forum.nginx.org/read.php?2,72993,72993#msg-72993)** > > I'm getting a lot of entries in my error\_log from memcache throwing a 404 and sending the request to the back end. 2010/04/08 21:07:50 \[alert\] 29914#0: \*3207 pcre\_exec() failed: -8 on "example.com" using "" while sending to... ---
**Author:** ![flash](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/f/f475e1/32.png) [@flash](https://www.ruby-forum.com/u/flash)\ **Post date:** [April 9, 2010, 11:31am UTC](https://www.ruby-forum.com/t/error-log-levels/186578/2 "2010-04-09T11:31:06Z")
Hello! On Thu, Apr 08, 2010 at 10:18:03PM -0400, flash wrote: > I’m getting a lot of entries in my error\_log from memcache > throwing a 404 and sending the request to the back end. > > 2010/04/08 21:07:50 29914#0: \*3207 pcre\_exec() failed: -8 on “[example.com](http://example.com)” using “” while sending to client, client: 66.249.71.23, server: \_, request: “GET [example.com](http://example.com) HTTP/1.1”, upstream: “memcached://127.0.0.1:11211”, host: “[example.com](http://example.com)” > > I’m assuming this is correct behavior since it cannot find the > requested url in memory; No, it isn’t. It’s unexpected error returned by pcre\_exec() function, and according to pcreapi manpage it means the following: ``` PCRE_ERROR_MATCHLIMIT (-8) The backtracking limit, as specified by the match_limit ``` field in a pcre\_extra structure (or defaulted) was reached. See the description above. You may want to investigate further why it happens. Default limit according to pcre docs is 10 million, so either you have completely wrong regex, or something wrong with your pcre library, or it’s nginx bug. > however, I have not been able to find > any error level descriptions in the docs - could you either fill > me in on what level I need to include on my conf file or point > me in the direction of where this info can be found? Logging levels from harmless to most critical are: debug, info, notice, warn, error, crit, alert, emerg It is not recommended to ignore any messages at crit level and above. First part of this list can be found here: > **[GitHub - nginxinc/nginx-wiki: ARCHIVED -- Source for the now archived NGINX Wiki...](https://github.com/nginxinc/nginx-wiki)** > > ARCHIVED -- Source for the now archived NGINX Wiki section of https://www.nginx.com Maxim D. ---
**Author:** ![flash](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/f/f475e1/32.png) [@flash](https://www.ruby-forum.com/u/flash)\ **Post date:** [April 10, 2010, 5:29am UTC](https://www.ruby-forum.com/t/error-log-levels/186578/3 "2010-04-10T05:29:29Z")
So I guess I need to start with my rewrites…here they are rewrite ^/([0-9]+)/([\_0-9a-zA-Z-]+)/?$ $theme/listing.php?mls=$1 last; rewrite ^/([0-9]+)/([\_0-9a-zA-Z-]+)+.html?$ $theme/listing.php?mls=$1 last; rewrite ^/([0-9]+)/?$ $theme/listing.php?mls=$1 last; rewrite ^/new-listings/new-listings-for-(+)-([0-9]+)-([\_0-9a-zA-Z-]+)/?$ $theme/newListings.php?month=$1&day=$2 last; here’s what I’m trying to capture [example.com/](http://example.com/)(mls number) [example.com/](http://example.com/)(mls number)/(mls address).html [example.com/](http://example.com/)(mls number)/(mls address)/ the mls number is either a 6 digit or a 7 digit number mls address is really irrelevant from a technical standpoint but needed for SEO These rewrites are working like I want them too but are they causing my prce errors? Flash Posted at Nginx Forum: > **[Re: error\_log levels](https://forum.nginx.org/read.php?2,72993,73353#msg-73353)** > > I'm getting a lot of entries in my error\_log from memcache throwing a 404 and sending the request to the back end. 2010/04/08 21:07:50 \[alert\] 29914#0: \*3207 pcre\_exec() failed: -8 on "example.com" using "" while sending to... ---
**Author:** ![flash](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/f/f475e1/32.png) [@flash](https://www.ruby-forum.com/u/flash)\ **Post date:** [April 10, 2010, 12:19pm UTC](https://www.ruby-forum.com/t/error-log-levels/186578/4 "2010-04-10T12:19:48Z")
Hello! On Fri, Apr 09, 2010 at 11:28:29PM -0400, flash wrote: > So I guess I need to start with my rewrites…here they are > > rewrite ^/([0-9]+)/([\_0-9a-zA-Z-]+)/?$ $theme/listing.php?mls=$1 last; > rewrite ^/([0-9]+)/([\_0-9a-zA-Z-]+)+.html?$ $theme/listing.php?mls=$1 last; This one will backtrack in an exponential way due to “(…+)+” construct. On long enough URL it will cause problems. Here is pcretest session which demonstrates the problem: $ pcretest PCRE version 7.9 2009-04-11 re\> !^/([0-9]+)/([\_0-9a-zA-Z-]+)+.html?$! data\> /1/1.html 0: /1/1.html 1: 1 2: 1 data\> /1/1.htmlx No match data\> /1/111111111111111111111111111111111111111111111111111111111.htmlx Error -8 […] > These rewrites are working like I want them too but are they > causing my prce errors? Yes they are. Maxim D. ---
**Author:** ![flash](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/f/f475e1/32.png) [@flash](https://www.ruby-forum.com/u/flash)\ **Post date:** [April 11, 2010, 4:22am UTC](https://www.ruby-forum.com/t/error-log-levels/186578/5 "2010-04-11T04:22:12Z")
Maxim, Thank you for your help, removing the second + in the highlighted line has removed that error from my logs. Flash Posted at Nginx Forum: > **[Re: error\_log levels](https://forum.nginx.org/read.php?2,72993,73651#msg-73651)** > > I'm getting a lot of entries in my error\_log from memcache throwing a 404 and sending the request to the back end. 2010/04/08 21:07:50 \[alert\] 29914#0: \*3207 pcre\_exec() failed: -8 on "example.com" using "" while sending to...