Dynamic Data Updates

Update the contents of ACL files, map files, or TLS ticket key files

In this example, we will update two map files every minute. One map file will be updated 100 milliseconds after HAProxy ALOHA starts or reloads, then every minute.

1. Create key/value pair map files with a text editor.

   • Create the file forbid.map, that contains a list of subnets and associated redirections:

     10.0.0.0/8     /maintenance.html
     192.168.0.0/16 /forbiden.html
     0.0.0.0        /deny.html

   • Create the file routes.map, that contains a list of domain names and associated HAProxy ALOHA backends:

     www.example.com     webservers
     api.example.com     apiservers
     static.example.com  cacheservers

2. In the HAProxy ALOHA web UI, select the Tools tab, then upload your map files in /etc/haproxy/extra/ through the File Manager.

   

3. To load the Update module, select the LB Layer 7 tab, then add the following line to the global section.

   global
     module-load update.so

4. Use your map files through map converters in frontend or backend sections.

   frontend fe_main
      bind *:80
      mode http
      http-request redirect location %[src,map_ip(/etc/haproxy/extra/forbid.map)] if { src,map_ip(/etc/haproxy/extra/forbid.map) -m found }
      use_backend %[req.hdr(host),map(/etc/haproxy/extra/routes.map,webservers)]

5. Create a dynamic-update section.

   Specify the paths to the local map files as the id.

   dynamic-update
      update id /etc/haproxy/extra/forbid.map url http://15.236.163.114/forbid.map delay 1m timeout 5s retries 3 map log
      update id /etc/haproxy/extra/routes.map url http://15.236.163.114/routes.map xdelay 1m 1m 100ms 5m timeout 5s retries 3 map log

   We won't include the dontlog-normal directive so that we can check in the logs that the files are correctly updated.

6. Upload updated versions of your map files to an endpoint through an FTP client or any other means.

   For example, upload your map files to http://15.236.163.114/forbid.map, and http://15.236.163.114/routes.map.

7. Reload the HAProxy service from the Services tab.

   In our example, the contents of the static forbid.map and routes.map files will be replaced in memory with the contents of the http://15.236.163.114/forbid.map and http://15.236.163.114/routes.map files, respectively, every minute.

   routes.map is updated 100 milliseconds after you reload HAProxy HAProxy ALOHA.

8. Check in the Logs tab that the files were successfully updated.

   

$ echo lb-update status | sudo socat stdio /var/run/haproxy.stat

 lb-update module status
 ------------------------------------------------------------------------------
 initialized:          yes

 SMP update
   configuration:      /var/state/haproxy.run:5
   entry:              /etc/haproxy/extra/forbid.map
   url:                http://15.236.163.114/forbid.map
   http status count:  0 17 0 0 0
   period/delay:       1m / 5s 10s 5s
   use modified:       no
   reload/retry count: 17 0 0 / 0 0
   reload time:        2021-09-09 10:53:11 / <NEVER> / <NEVER>
   download time:      2021-09-09 10:53:11 / <NEVER>
   next update in:     53s

 SMP update
   configuration:      /var/state/haproxy.run:6
   entry:              /etc/haproxy/extra/routes.map
   url:                http://15.236.163.114/routes.map
   http status count:  0 16 0 0 0
   period/delay:       1m / 1m 0.100s 5m
   use modified:       no
   reload/retry count: 16 0 0 / 0 0
   reload time:        2021-09-09 10:53:06 / <NEVER> / <NEVER>
   download time:      2021-09-09 10:53:06 / <NEVER>
   next update in:     48s

How the Update module works

At startup, HAProxy ALOHA loads the content of map files or ACL files from a designated file.

If there is an update directive set up to update this content, HAProxy ALOHA downloads the new content from a given endpoint after the designated period of time.

• HAProxy ALOHA updates the content of the map files or ACL files only after the file downloads correctly.

• If HAProxy ALOHA cannot connect to the server, it retries the number of times you specify.

Update module directive syntax

The Update configuration section, dynamic-update, can contain one or several update directives.

update id <id> url <url> [delay <delay> | xdelay <delay start next retry>] [timeout <tmout>] [retries <nb>] [modified] [source <addr>[:<port>]] [log] [dontlog-normal] [map] [tls-ticket-keys] [param*]

Optional TLS server parameters

You can also specify additional HAProxy ALOHA configuration parameters available for the server directive.