# Conditionally disable keepalives **URL:** \ **Category:** NGINX\ **Created:** [September 17, 2010, 6:28pm UTC](https://www.ruby-forum.com/t/conditionally-disable-keepalives/195152 "2010-09-17T18:28:08Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![rmac217](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/bc8723/32.png) [@rmac217](https://www.ruby-forum.com/u/rmac217)\ **Post date:** [September 17, 2010, 6:28pm UTC](https://www.ruby-forum.com/t/conditionally-disable-keepalives/195152/1 "2010-09-17T18:28:08Z")
Is it possible to conditionally disable keep-alives via some sort of configuration? I have a customer with a buggy proxy that they cannot fix short-term, but I do not want to disable keepalives entirely for every user. With keepalives enabled, they intermittently see “raw” HTTP streams in the browser, headers and all. Thousands of other customers have no issues, of course, as they aren’t using this particular proxy (Trend Micro Viruswall 6). The “keepalive\_timeout” directive will not accept a variable value. Right now I have a configuration that conditionally adds a “Connection: close” header based on $remote\_addr, but that gets sent in addition to the “Connection: keepalive” header set by nginx. While it seems to work for this particular buggy proxy, sending multiple “Connection” headers is also an HTTP specification violation, I think. The only other thing I can think of to do is a rewrite to a different server or location with “keepalive\_timeout 0” specified, but will that even work, or are keepalives handled at the connection layer? ## nginx 0.7.65 on Ubuntu 10.04 RPM ---
**Author:** ![rmac217](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/bc8723/32.png) [@rmac217](https://www.ruby-forum.com/u/rmac217)\ **Post date:** [September 17, 2010, 6:35pm UTC](https://www.ruby-forum.com/t/conditionally-disable-keepalives/195152/2 "2010-09-17T18:35:09Z")
On Fri, 2010-09-17 at 11:27 -0500, Ryan M. wrote: > Right now I have a configuration that conditionally adds a > “Connection: close” header based on $remote\_addr, but that gets sent > in addition to the “Connection: keepalive” header set by nginx. While > it seems to work for this particular buggy proxy, sending multiple > “Connection” headers is also an HTTP specification violation, I think. > > The only other thing I can think of to do is a rewrite to a different > server or location with “keepalive\_timeout 0” specified, but will that > even work, or are keepalives handled at the connection layer? > > nginx 0.7.65 on Ubuntu 10.04 Or you could run a second Nginx instance between them and the main Nginx instance. Cliff – ---
**Author:** ![rmac217](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/bc8723/32.png) [@rmac217](https://www.ruby-forum.com/u/rmac217)\ **Post date:** [September 17, 2010, 7:21pm UTC](https://www.ruby-forum.com/t/conditionally-disable-keepalives/195152/3 "2010-09-17T19:21:23Z")
On Fri, Sep 17, 2010 at 11:34 AM, Cliff W. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > Or you could run a second Nginx instance between them and the main Nginx > instance. I thought about that… I suppose I could even have the same nginx instance proxy to itself, as the source IP would change to localhost on the subrequest, but it seems wasteful and potentially brittle. They cannot configure their proxy to send HTTP 1.0 requests, even though it clearly does not support HTTP 1.1 correctly. And of course they say “they have no problems with other sites”, which I think likely not true. I could, I suppose, even give them a different hostname to work with, but that would likely require many application-layer changes as well. – RPM ---
**Author:** ![rmac217](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/bc8723/32.png) [@rmac217](https://www.ruby-forum.com/u/rmac217)\ **Post date:** [September 17, 2010, 7:46pm UTC](https://www.ruby-forum.com/t/conditionally-disable-keepalives/195152/4 "2010-09-17T19:46:33Z")
On 17/09/2010 17:27, Ryan M. wrote: > Is it possible to conditionally disable keep-alives via some sort of > configuration? > I would suggest putting the keepalive\_timeout directive inside an if > block, but it’s not permitted. Igor/Maxim : Is there a good reason why keepalive\_timeout cannot be set inside a server or location if block? Cheers, Marcus. ---
**Author:** ![rmac217](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/bc8723/32.png) [@rmac217](https://www.ruby-forum.com/u/rmac217)\ **Post date:** [September 17, 2010, 8:38pm UTC](https://www.ruby-forum.com/t/conditionally-disable-keepalives/195152/5 "2010-09-17T20:38:04Z")
On Fri, Sep 17, 2010 at 12:20 PM, Ryan M. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > On Fri, Sep 17, 2010 at 11:34 AM, Cliff W. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > > Or you could run a second Nginx instance between them and the main Nginx > > instance. > > I thought about that… I suppose I could even have the same nginx > instance proxy to itself, as the source IP would change to localhost > on the subrequest, but it seems wasteful and potentially brittle. So, the “proxy back to another nginx” (in this case the same instance) Cliff suggested seems to be working, and I get a “Connection: close” header for the IPs I am interested in, and keepalives seem to be off. However, I do not get see the header I add in my special location, even though I know it is hitting that location via rewrite. Is proxy\_pass [http://127.0.0.1](http://127.0.0.1) treated specially by nginx somehow? I would also expect to see two entries in the log files for every request, but I do not. Here is what I have (streamlined config) server { if ($remote\_addr ~ “^(111.111.111.111|222.222.222.222)$”) { rewrite ^(.\*)$ /nokeepalive$1; } location / #and and many other locations location /nokeepalive { keepalive\_timeout 0; add\_header “X-NoKeepalive-Proxy” “true”; proxy\_set\_header Host $host; #proxy back to myself at original request URI rewrite /nokeepalive(.\*)$ $1; proxy\_pass [http://127.0.0.1](http://127.0.0.1); } } – RPM ---
**Author:** ![rmac217](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/bc8723/32.png) [@rmac217](https://www.ruby-forum.com/u/rmac217)\ **Post date:** [September 17, 2010, 8:49pm UTC](https://www.ruby-forum.com/t/conditionally-disable-keepalives/195152/6 "2010-09-17T20:49:12Z")
Hello! On Fri, Sep 17, 2010 at 06:45:33PM +0100, Eugaia wrote: > On 17/09/2010 17:27, Ryan M. wrote: > > > Is it possible to conditionally disable keep-alives via some sort of > > configuration? > > I would suggest putting the keepalive\_timeout directive inside an if > > block, but it’s not permitted. > > Igor/Maxim : Is there a good reason why keepalive\_timeout cannot be > set inside a server or location if block? There is a good reason to disable anything but rewrite directives in “if” blocks. > **[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:** ![rmac217](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/bc8723/32.png) [@rmac217](https://www.ruby-forum.com/u/rmac217)\ **Post date:** [September 17, 2010, 9:11pm UTC](https://www.ruby-forum.com/t/conditionally-disable-keepalives/195152/7 "2010-09-17T21:11:26Z")
On 17/09/2010 19:47, Maxim D. wrote: > nside a server or location if block? > There is a good reason to disable anything but rewrite directives > in “if” blocks. > I know about the ‘if is evil’ idea, but so long as you know what will > happen (i.e. that if blocks don’t behave like you might expect them to), > is there any other inherent problem caused? Was the decision to not allow many statements inside if blocks basically made because to do so would probably mean that configurations might do something unconventional (and other than what the administrator probably would expect them to do), rather than for any other inherent problem? Thanks, Marcus.