Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

We recently moved a new server and are facing the slow upload issues . We suspect this because of firewall . how do I make sure applications like ftp,curl become faster with firewall.

Any inputs regarding the disabling the firewall/bypassing the firewall or any other inputs is greatly appreciated .



We recently migrated from one server to the another .Since then we are seeing the file uploads done through ( http client (phpclasses), CURL ) is taking considerably more time . For eg for a 5MB file in the earlier server it was taking 3 seconds. But in the new server it is taking about 100 seconds . Please note that I am running a PHP daemon to upload the files. We first tried the PHP classes http client and now we are trying PHP CURL .But still we find the same issue. When we upload files > 200MB its taking almost 1hr.Both the server have 100Mbps uplink. so connection speed is not the issue.The file transfer are same if I use PHP curl or the curl command .

Are we missing any setting on the server ( PHP configuration) or module or firewall ? Has anyone experienced such a issue before ? Any inputs is appreciated.

share|improve this question
What makes you suspect a firewall? – Shane Madden Jan 13 '12 at 5:56
on the internet there are so many posts on this . I am not sure though.I also see some CRC erros on the input interface. – user26202 Jan 13 '12 at 6:00

Generally firewalls will either stop connections or allow them - not slow them down.

In the absence of a lot more information about what's going on here, it's impossible to make an even an educated guess as to what's happening - if you don't know how to start investigating the problem then go speak to the people whom you are paying to provide support for the service.

One of the many things you've not mentioned is where the firewall is - if it is at your end, then provide some info about how it is configured. If it is at the remote end, then you won't have access to the config and won't be able to change it - again, speak to the people supporting it.

You've also not provided any information about the location of the old and new server relative to where you're uploading data from nor the configuration of your internet connection.

Nor have you provided any info about how the problem varies by file size (a consistent delay for all operations regardless of size would suggest a DNS issue, a delay increasing with file size would indicate a latency / bandwidth / window scaling issue)

share|improve this answer
I added more info .Kindly have a look – user26202 Jan 13 '12 at 17:00
Sorry - still not enough information. Try plotting the upload time against file size to get real measurements of bandwidth and latency. – symcbean Jan 17 '12 at 9:29

Your Answer


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.