# Mediacache : ERROR 500 - java.lang.NullPointerException and Bad file descriptor **URL:** \ **Category:** Wowza Streaming Engine\ **Tags:** server-administration\ **Created:** [September 17, 2012, 6:03pm UTC](https://community.wowza.com/t/mediacache-error-500-java-lang-nullpointerexception-and-bad-file-descriptor/38929 "2012-09-17T18:03:54Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Super\_Masita](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Super\_Masita](https://community.wowza.com/u/Super_Masita)\ **Post date:** [September 17, 2012, 6:03pm UTC](https://community.wowza.com/t/mediacache-error-500-java-lang-nullpointerexception-and-bad-file-descriptor/38929/1 "2012-09-17T18:03:54Z")
Hi, I can see many 500 errors in my access logs. These errors are frequent but the videos are accessoble: i can play them without any problems. - What does this errors means? - Could this be a cause for our customers not to play the videos? Thank you very much for your help! 🙂 ```auto 2012-09-17 17:57:37 GMT-03:00 comment server ERROR 500 - MediaCacheReaderCached.read[incache,2012/09/17/eeeeeee160912-500.mp4,null,[B@57114a66]: java.lang.NullPointerException - - - 1732659.71 - - - - - - - - - - - - -- - - - - - - - - - - - 2012-09-17 17:57:37 GMT-03:00 comment server ERROR 500 - MediaCacheReaderCached.read[incache,2012/09/17/nnnnn360.mp4,null,[B@56dca5d5]: java.lang.NullPointerException - - - 1732660.383 - - - - - - - - - - - - - -- - - - - - - - - - - 2012-09-17 17:57:39 GMT-03:00 comment server ERROR 500 - MediaCacheReaderCached.read[incache,2012/09/17/zzzz-160912-720ok.mp4,null,[B@3f497b95]: java.io.IOException: Bad file descriptor - - - 1732661.925 - - - - - - - - - - -- - - - - - - - - - - - - - 2012-09-17 17:57:39 GMT-03:00 comment server ERROR 500 - MediaCacheReaderCached.read[incache,2012/08/17/yyyy-720.mp4,null,[B@33727cf6]: java.lang.NullPointerException - - - 1732662.249 - - - - - - - - - - - - - -- - - - - - - - - - - 2012-09-17 17:57:39 GMT-03:00 comment server ERROR 500 - MediaCacheReaderCached.read[incache,2012/09/15/xxxx-140912-360-500.mp4,null,[B@55f61ce4]: java.io.IOException: Bad file descriptor - - - 1732662.316 - - - - - - - - - - -- - - - - - - - - - - - - - ``` ---
**Author:** ![Super\_Masita](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Super\_Masita](https://community.wowza.com/u/Super_Masita)\ **Post date:** [September 19, 2012, 11:50am UTC](https://community.wowza.com/t/mediacache-error-500-java-lang-nullpointerexception-and-bad-file-descriptor/38929/2 "2012-09-19T11:50:09Z")
Anyone? 🙂 Thks! ---
**Author:** ![Richard\_Lanham](https://avatars.discourse-cdn.com/v4/letter/r/c68b51/32.png) [@Richard\_Lanham](https://community.wowza.com/u/Richard_Lanham)\ **Post date:** [September 19, 2012, 3:14pm UTC](https://community.wowza.com/t/mediacache-error-500-java-lang-nullpointerexception-and-bad-file-descriptor/38929/3 "2012-09-19T15:14:02Z")
This could be an intermittent network problem between Wowza and the content server, or some problem with the content server itself. Richard ---
**Author:** ![Richard\_Lanham](https://avatars.discourse-cdn.com/v4/letter/r/c68b51/32.png) [@Richard\_Lanham](https://community.wowza.com/u/Richard_Lanham)\ **Post date:** [September 19, 2012, 5:40pm UTC](https://community.wowza.com/t/mediacache-error-500-java-lang-nullpointerexception-and-bad-file-descriptor/38929/4 "2012-09-19T17:40:30Z")
Maybe, but I don’t think so. Is traffic heavy? Is there a correlation with heavy load? You said you don’t notice a problem with streaming. Richard ---
**Author:** ![Richard\_Lanham](https://avatars.discourse-cdn.com/v4/letter/r/c68b51/32.png) [@Richard\_Lanham](https://community.wowza.com/u/Richard_Lanham)\ **Post date:** [October 31, 2012, 1:01pm UTC](https://community.wowza.com/t/mediacache-error-500-java-lang-nullpointerexception-and-bad-file-descriptor/38929/5 "2012-10-31T13:01:35Z")
Here is some info [https://www.wowza.com/forums/showthread.php?12036-S3-content-plays-but-logs-error-and-doesn-t-record-sc-stream-bytes-on-destroy](https://www.wowza.com/forums/showthread.php?12036-S3-content-plays-but-logs-error-and-doesn-t-record-sc-stream-bytes-on-destroy) > I believe there is a small concurrency issue with MediaCache that leads to this log statement. I do not believe it leads to a problem. It will most likely be addressed in a future release to MediaCache. I will try to look at this sooner rather than later. I see the problem. I just need to consider how to correctly address it. > > Charlie ---
**Author:** ![Super\_Masita](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Super\_Masita](https://community.wowza.com/u/Super_Masita)\ **Post date:** [September 19, 2012, 2:33pm UTC](https://community.wowza.com/t/mediacache-error-500-java-lang-nullpointerexception-and-bad-file-descriptor/38929/6 "2012-09-19T14:33:26Z")
> This could be an intermittent network problem between Wowza and the content server, or some problem with the content server itself. > > Richard Thanks for the reply! This could be cause by disk contention (high i/o) on the Wowza server? ---
**Author:** ![Super\_Masita](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Super\_Masita](https://community.wowza.com/u/Super_Masita)\ **Post date:** [October 1, 2012, 1:50pm UTC](https://community.wowza.com/t/mediacache-error-500-java-lang-nullpointerexception-and-bad-file-descriptor/38929/7 "2012-10-01T13:50:59Z")
> Maybe, but I don’t think so. Is traffic heavy? Is there a correlation with heavy load? You said you don’t notice a problem with streaming. > > Richard The server is traffic heavy and has heavy load due to disk I/O. I dont notice any problems with the videos, but im not sure of anyone else does. ---
**Author:** ![Super\_Masita](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Super\_Masita](https://community.wowza.com/u/Super_Masita)\ **Post date:** [October 16, 2012, 11:41pm UTC](https://community.wowza.com/t/mediacache-error-500-java-lang-nullpointerexception-and-bad-file-descriptor/38929/8 "2012-10-16T23:41:02Z")
Richard, What does exactly this error means? ---
**Author:** ![Super\_Masita](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Super\_Masita](https://community.wowza.com/u/Super_Masita)\ **Post date:** [October 30, 2012, 1:04pm UTC](https://community.wowza.com/t/mediacache-error-500-java-lang-nullpointerexception-and-bad-file-descriptor/38929/9 "2012-10-30T13:04:04Z")
What does exactly this error means? thks!! ---
**Author:** ![Super\_Masita](https://avatars.discourse-cdn.com/v4/letter/s/ec9cab/32.png) [@Super\_Masita](https://community.wowza.com/u/Super_Masita)\ **Post date:** [November 1, 2012, 6:09pm UTC](https://community.wowza.com/t/mediacache-error-500-java-lang-nullpointerexception-and-bad-file-descriptor/38929/10 "2012-11-01T18:09:17Z")
Is it possible to ask Charlie if the issue its going to be solved? Ive tried reaching him over PM but his account is full… Thanks!