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• If you choose to let your traffic visit the HTTP version of your site, the proxy cache servers will serve content that has been stored on them. This is a useful feature to help improve site performance.
• If you are making updates to your site, you'll want to be sure that you flush any cached content that is sitting inside the proxy cache servers or your newly updated content can take up to ~2 hours to be visible. A script has been provided below, with instructions on how to install and use it to help automate flushing the cached content in the proxy cache servers.

• If you are interested in further assistance with this, please visit our office hours that are held every Tuesday from 1:00-2:30pm in FAC 30 or send an email to web@utexas.edu.

  Please visit /wiki/spaces/utweb/pages/63867019 for more updated scripts.

The following script is what we will be using to flush the proxy server's cached content. This file is located at /utweb/common/src/examples/clearcache.sh - Below the script are instructions for installing and using it. 

#!/bin/sh
#
# Example of automating the process of purging the HTTP proxy cache for
# a UT Web content site.
#
# This assumes:
#    * the script is running on the UT Web panel server
#    * The script is being run as the UT Web site account
#    * the URL to purge is the site's main URL (utwNNNNN.utweb.utexas.edu)
#    * all sub-URL's of the main site should be purged as well ($site/*)
#
# Season to taste.
#
siteuser=`whoami`
site=http://$siteuser.utweb.utexas.edu
urlstopurge="$site"

utweb_prod_balancers="
utweb-px-z1-p01.its.utexas.edu
utweb-px-z1-p02.its.utexas.edu
"
sitealiases=$(grep 'ServerAlias' /etc/httpd/vhost.d/`whoami`.utweb.utexas.edu.conf | cut
-f 2 -d ' ' | grep -vP 'utw\d{5}' |xargs -0 |sort -u)

if  [ -z "$sitealiases" ] ; then
    echo "=== There are no domain aliases for this site account ==="
else echo === $sitealiases ===
fi

# Purge cache for utwNNNNN.utweb.utexas.edu hostname
for b in $utweb_prod_balancers; do
    id=`echo $b | sed s/.its.utexas.edu/_http/`
    for u in $urlstopurge ; do
    echo === $b $site
        curl -v \
        --cookie "balancer_id=$id" \
        -X PURGE \
        -D - "$u/*"
    done
done

# Purge cache for any additional hostnames
for b in $utweb_prod_balancers; do
    id=$(echo $b | sed s/.its.utexas.edu/_http/)
    for u in $sitealiases; do
    echo === $b $sitealiases
        curl -v \
        --cookie "balancer_id=$id" \
        -X PURGE \
        -D - "$u/*"
    done
done
 

1. From a SSH client (Windows) or Terminal (OS X) window, you will need to connect to your site account's home directory on the panel server via a SSH connection:

   Code Block
   language bash
   ssh <utw10NNNNN>@panel.utweb.utexas.edu

   
   **NOTE: These next steps assume that you are still in your home directory and have not changed your working directory upon logging in.

2. Copy the clearcache.sh file in to your site account's home directory: To do this, type the following in to your command line:

   Code Block
   language bash
   cp /utweb/common/src/examples/clearcache.sh clearcache.sh

3. If you have domains stamped to your site, please continue to step #4; otherwise, skip to step #8 if you do not have any additional domains associated with your site.

4. Type the following command in your command line to edit the clearcache script:

   Code Block
   nano ~/clearcache.sh

5. This will bring up the nano text editor in your terminal window. From here, you will need to navigate the file with your keyboards arrow keys. Find the line that says urlstopurge="$site"

6. Once you have navigated to that line, put a space after $site and add the domains you have stamped with your site. Separate each entry you add with a space. If your site can be visited with www, please include that name as well.

7. When you are finished adding your domains, press "Ctrl+o" on your keyboard. Nano will then repeat to you the file it is making these changes to. Press "Enter" on your keyboard to confirm the file and save your changes.

8. Now that the file is in your home directory (and your domains have been optionally added), we need to change the permissions of it the script to be executable. To do this, type the following in to your command line:

   Code Block
   language bash
   chmod 750770 ~/clearcache.sh

9. Now that the file is executable, run the script by typing the following in to your command line:

   Code Block
   language bash
   .~/clearcache.sh

   Real Output (no additional domains have been added to the script, so the cache is only being cleared for utw10373.utweb.utexas.edu):

   No Format
   language bash theme Midnight
   === utweb-px-z1-p01.its.utexas.edu http://utw10373.utweb.utexas.edu * About to connect() to utw10373.utweb.utexas.edu port 80 (#0) * Trying 128.83.21.174... connected * Connected to utw10373.utweb.utexas.edu (128.83.21.174) port 80 (#0) > PURGE /* HTTP/1.1 > User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.18 Basic ECC zlib/1.2.3 libidn/1.18 libssh2/1.4. > Host: utw10373.utweb.utexas.edu > Accept: */* > Cookie: balancer_id=utweb-px-z1-p01_http > < HTTP/1.1 204 No Content HTTP/1.1 204 No Content < Server: nginx Server: nginx < Date: Wed, 27 Apr 2016 17:55:41 GMT Date: Wed, 27 Apr 2016 17:55:41 GMT < X-CacheServer: 172.17.99.42 X-CacheServer: 172.17.99.42 < Set-Cookie: balancer_id=utweb-px-z1-p01_http|VyD9I|VyD9I; path=/ Set-Cookie: balancer_id=utweb-px-z1-p01_http|VyD9I|VyD9I; path=/ < * Connection #0 to host utw10373.utweb.utexas.edu left intact * Closing connection #0 === utweb-px-z1-p02.its.utexas.edu http://utw10373.utweb.utexas.edu * About to connect() to utw10373.utweb.utexas.edu port 80 (#0) * Trying 128.83.21.174... connected * Connected to utw10373.utweb.utexas.edu (128.83.21.174) port 80 (#0) > PURGE /* HTTP/1.1 > User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.18 Basic ECC zlib/1.2.3 libidn/1.18 libssh2/1.4.2 > Host: utw10373.utweb.utexas.edu > Accept: */* > Cookie: balancer_id=utweb-px-z1-p02_http >  < HTTP/1.1 204 No Content HTTP/1.1 204 No Content < Server: nginx Server: nginx < Date: Wed, 27 Apr 2016 17:55:41 GMT Date: Wed, 27 Apr 2016 17:55:41 GMT < X-CacheServer: 172.17.99.43 X-CacheServer: 172.17.99.43 < Set-Cookie: balancer_id=utweb-px-z1-p02_http|VyD9I|VyD9I; path=/ Set-Cookie: balancer_id=utweb-px-z1-p02_http|VyD9I|VyD9I; path=/ < * Connection #0 to host utw10373.utweb.utexas.edu left intact * Closing connection #0

10. Check to see if the proxy caches were flushed by typing this in to your command line:

    Code Block
    language bash
    curl -vI utwNNNNN.utweb.utexas.edu OR curl -vI <your domain here>

    Real Output:

    No Format
    language bash theme Midnight
    * About to connect() to utw10373.utweb.utexas.edu port 80 (#0) * Trying 128.83.21.174... connected * Connected to utw10373.utweb.utexas.edu (128.83.21.174) port 80 (#0) > HEAD / HTTP/1.1 > User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.18 Basic ECC zlib/1.2.3 libidn/1.18 libssh2/1.4.2 > Host: utw10373.utweb.utexas.edu > Accept: */* > < HTTP/1.1 200 OK HTTP/1.1 200 OK < Server: nginx Server: nginx < Date: Wed, 27 Apr 2016 17:45:56 GMT Date: Wed, 27 Apr 2016 17:45:56 GMT < Content-Type: text/html; charset=UTF-8 Content-Type: text/html; charset=UTF-8 < Content-Length: 19 Content-Length: 19 < Set-Cookie: cache_id=36e1dd7a55420bbdaed5922d061460e7; expires=Wed, 27-Apr-16 18:45:56 GMT; path=/ Set-Cookie: cache_id=36e1dd7a55420bbdaed5922d061460e7; expires=Wed, 27-Apr-16 18:45:56 GMT; path=/ < Last-Modified: Wed, 27 Apr 2016 16:58:09 GMT Last-Modified: Wed, 27 Apr 2016 16:58:09 GMT < ETag: "abdfdae70c71675e-13-5317a507b7971" ETag: "abdfdae70c71675e-13-5317a507b7971" < X-BackendServer: 172.17.99.35:80 X-BackendServer: 172.17.99.35:80 < X-CacheServer: 172.17.99.43 X-CacheServer: 172.17.99.43 < X-Cache: MISS X-Cache: MISS < Accept-Ranges: bytes Accept-Ranges: bytes < Set-Cookie: balancer_id=utweb-px-z1-p02_http|VyD61|VyD61; path=/ Set-Cookie: balancer_id=utweb-px-z1-p02_http|VyD61|VyD61; path=/ < Cache-control: private Cache-control: private < * Connection #0 to host utw10373.utweb.utexas.edu left intact * Closing connection #0

11. Pay attention to the bottom of the output where you will see something like this to confirm the cache was flushed on that proxy cache server:

    No Format
    < X-Cache: MISS X-Cache: MISS

12. Check your site for updated content!

...