Virtual Hosting
Virtual hosting is built in to AOLserver 4. (See below for version 3.x recipes)
Say you want to run 2 sites from one IP address. You'll need 3 config files - frontend.tcl, backend1.tcl and backend2.tcl. The frontend will run on port 80 and proxy requests to the backend servers depending on the hostname in the Header. You'll actually only run 1 AOLserver process. When you start nsd, you'll feed it frontend.tcl. The first thing frontend.tcl does is to read backend1.tcl and backend2.tcl. It sets up those virtual servers and then sets some global parameters.
Here's how I set up my directory structure:
/home/vinod/web/
backend1/
backend1.tcl
log/
www/
index.adp
backend2/
backend2.tcl
log/
www/
index.adp
frontend/
frontend.tcl
log/
And here are the files:
frontend.tcl
ns_log notice "Starting to read frontend config file..."
source /home/vinod/web/backend1/backend1.tcl source /home/vinod/web/backend2/backend2.tcl
ns_log notice "Done loading backend server configs..."
# Load nssock globally ns_section ns/modules ns_param nssock /usr/local/aolserver/bin/nssock.so
ns_section ns/module/nssock ns_param port 80 ns_param hostname myhostname.example.com ns_param address 0.0.0.0 ns_param defaultserver backend1
# Map headers to server-name ns_section ns/module/nssock/servers ns_param backend1 backend1.com ns_param backend1 backend1.com:80 ns_param backend2 backend2.com ns_param backend2 backend2.com:80 ns_param backend2 myotherdomain.com ns_param backend2 myotherdomain.com:80
ns_section ns/servers ns_param backend1 "My First Example Site" ns_param backend2 "My Second Example Site"
# Global server parameters ns_section ns/parameters ns_param serverlog /home/vinod/web/frontend/log/error.log ns_param home /usr/local/aolserver
ns_section ns/threads ns_param stacksize expr 128*1024 ;# Per-thread stack size.
ns_section ns/mimetypes ns_param default "*/*" ;# MIME type for unknown extension. ns_param noextension "*/*" ;# MIME type for missing extension.
ns_log notice "nsd.tcl: finished reading frontend config file."
backend1.tcl and backend2.tcl (The only difference is the first line)
set server "backend1" ;# or "backend2" for backend2.tcl ns_log notice "Starting to read $server config file..."
set db_name $server
set serverroot "/home/vinod/web/${server}"
set bindir [[file dirname [ns_info nsd]]]
set pageroot ${serverroot}/www
# Tcl Configuration
ns_section ns/server/${server}/tcl
ns_param library ${serverroot}/tcl
# Server parameters
ns_section ns/server/${server}
ns_param directoryfile index.tcl,index.adp,index.html,index.htm
ns_param pageroot $pageroot
# ADP (AOLserver Dynamic Page) configuration
ns_section ns/server/${server}/adp
ns_param map /*.adp ;# Extensions to parse as ADP's
ns_param defaultparser fancy
ns_section ns/server/${server}/adp/parsers
ns_param fancy ".adp"
# Database drivers
ns_section "ns/db/drivers"
ns_param postgres ${bindir}/nspostgres.so
ns_section ns/db/pools
ns_param ${server}pool1 "$server Pool 1"
ns_param ${server}pool2 "$server Pool 2"
ns_section ns/db/pool/${server}pool1
ns_param driver postgres
ns_param datasource localhost::${db_name}
ns_param user vinod
ns_section ns/db/pool/${server}pool2
ns_param driver postgres
ns_param datasource localhost::${db_name}
ns_param user vinod
ns_section ns/server/${server}/db
ns_param pools "${server}pool1,${server}pool2"
ns_param defaultpool ${server}pool1
# Access log -- nslog
ns_section ns/server/${server}/module/nslog
ns_param file ${serverroot}/log/access.log
# Modules to load
ns_section ns/server/${server}/modules
ns_param nsdb ${bindir}/nsdb.so
ns_param nslog ${bindir}/nslog.so
ns_log notice "Finished reading $server config file."
This sets up 2 pretty plain virtual hosts. Once you get this setup working, you can configure backend1.tcl and backend2.tcl to your heart's desire.
Note that you can map multiple Headers to 1 server. It's also important to note that the server's error log is specified in ns/parameters, so you can't specifiy a separate error.log for each backend server.
Start your server:
root:/home/vinod/web/frontend# /usr/local/aolserver/bin/nsd -t frontend.tcl -b 0.0.0.0:80 -u nobody -g web
Hope this helps - Vinod Kurup 2005-07-21
AOLserver 3.x
The following three patches are required to get nsvhr/nssock and nsvhr/nsunix working under AOLserver 3.5.x:
- http://panoptic.com/aolserver/dossy-aolserver3_5_x-patch (1313 bytes)
- http://panoptic.com/aolserver/dossy-nsunix-patch (21909 bytes)
- http://panoptic.com/aolserver/dossy-nsvhr-patch (1945 bytes)
NOTE: As of 2002-11-23, the changes to the core are no longer necessary and the changes to nsunix and nsvhr have been committed to CVS. Look for tag nsunix3_5 and nsvhr3_5.
In the nsvhr server's nsd.tcl:
ns_section "ns/server/${servername}/modules"
...
ns_param nssock nssock.so
ns_param nsvhr nsvhr.so
#
# Virtual Hosting redirector -- nsvhr
#
ns_section "ns/server/${servername}/module/nsvhr"
ns_param Method "GET" ;# Methods allowed to proxy
ns_param Method "POST" ;# Methods allowed to proxy (can have >1)
ns_param Method "HEAD" ;# Methods allowed to proxy (can have >1)
ns_param Timeout 60 ;# Timeout waiting for back-end
# Register hosts to proxy
ns_section "ns/server/${servername}/module/nsvhr/maps"
ns_param "www.domain.com" "unix://domain.com.nsunix" ns_param "www.domain.com:80" "unix://domain.com.nsunix" ns_param "domain.com" "unix://domain.com.nsunix" ns_param "domain.com:80" "unix://domain.com.nsunix"
In the nssock or nsunix virtual host's nsd.tcl:
ns_section "ns/server/${servername}/module/nsunix"
ns_param Hostname www.domain.com
ns_param Port 80
ns_param Location http://www.domain.com
ns_param SocketFile domain.com.nsunix
ns_section "ns/server/${servername}/modules"
...
ns_param nsunix nsunix.so
