Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

I am getting the following error intermittently on my server:

**Proxy Error** 
The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request GET /.
Reason: Error reading from remote server

The error logs show the following:

[Sun Feb 06 03:06:00 2011] [error] [client 82.43.154.57] proxy: Error reading from remote server returned by /login, referer: https://demo.XXXXX.us/
[Sun Feb 06 03:06:30 2011] [error] [client 82.43.154.57] (70007)The timeout specified has expired: proxy: error reading status line from remote server XXXXX.us
[Sun Feb 06 03:06:30 2011] [error] [client 82.43.154.57] proxy: Error reading from remote server returned by /
[Sun Feb 06 03:13:31 2011] [error] [client 82.43.154.57] (70007)The timeout specified has expired: proxy: error reading status line from remote server XXXXX.us
[Sun Feb 06 03:13:31 2011] [error] [client 82.43.154.57] proxy: Error reading from remote server returned by /

The server normally runs on around 150mb of free memory. Could these errors be caused by the lack of memory?

Would appreciate any ideas people have.

Thank you.

share|improve this question

2 Answers 2

It sounds like the server you are proxying to is timing out. I.e., https://demo.XXXXX.us is not responding. Have you verified that the you're proxying to is up?

share|improve this answer
    
I'm not too knowledgeable on this area, but if you are asking if server running demo.XXXXX.us is up, then yes. It is an intermittent error. –  KitCarrau Feb 6 '11 at 18:33
    
Do you have any sort of persistence monitoring? The backend server is definitely not able to be reached. I would setup pingdom/nagios/whatever to check to make sure that its up when you expect it. –  Andrew M. Feb 6 '11 at 19:04
up vote 0 down vote accepted

Thank you for the responses. I have found the cause of the error.

We are using Pear Mailer which uses a queue to stack emails ready for sending with a cron job. There was an error in the Pear script which was being called on every action on our site (making posts, sending messages etc..). Pear was crashing which in turn crashed the browser resulting in the above errors.

Disabling Pear resolved the problem, and tweaking the code got it working again. It took so long to find the issue as we never thought Pear Mailer could cause such a response.

Thanks again for your help.

Chris.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.