Configuring Blogs on a multi site Magento setup - apache

Question

I have two websites say abc.com and pqr.com running from the same Magento installation. Now I want to create blogs for each of those domains through wordpress for which I have created a folder "blogs" in the root Magento directory and installed two instances of wordpress in folders named blogs/abc and blogs/pqr.
How do I configure my .htaccess or index.php in the root directory so that requests to www.abc.com/blog and www.pqr.com/blog are routed to the folders blogs/abc and blogs/pqr respectively.
Please note that I want my blog URL's to be of the form abc.com/blog and not blog.abc.com
############################################
## you can put here your magento root folder
## path relative to web root
RewriteBase /
############################################
## uncomment next line to enable light API calls processing
# RewriteRule ^api/([a-z][0-9a-z_]+)/?$ api.php?type=$1 [QSA,L]
############################################
## rewrite API2 calls to api.php (by now it is REST only)
RewriteRule ^api/rest api.php?type=rest [QSA,L]
############################################
## workaround for HTTP authorization
## in CGI environment
RewriteRule .* - [E=HTTP_AUTHORIZATION:%{HTTP:Authorization}]
############################################
## TRACE and TRACK HTTP methods disabled to prevent XSS attacks
RewriteCond %{REQUEST_METHOD} ^TRAC[EK]
RewriteRule .* - [L,R=405]
############################################
## redirect for mobile user agents
#RewriteCond %{REQUEST_URI} !^/mobiledirectoryhere/.*$
#RewriteCond %{HTTP_USER_AGENT} "android|blackberry|ipad|iphone|ipod|iemobile|opera mobile|palmos|webos|googlebot-mobile" [NC]
#RewriteRule ^(.*)$ /mobiledirectoryhere/ [L,R=302]
############################################
## always send 404 on missing files in these folders
RewriteCond %{REQUEST_URI} !^/(media|skin|js)/
############################################
## never rewrite for existing files, directories and links
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-l
#Redirect Blogs
#RewriteCond %{HTTP_HOST} ^(?:www\.)?(abc|pqr)\.com$ [NC]
#RewriteRule ^blog(?:/(.*))?$ /blogs/%1/$1 [NC,L]
############################################
## rewrite everything else to index.php
RewriteRule .* index.php [L]
</IfModule>

Answer 1

Add the following to your root .htaccess:
RewriteEngine on
RewriteCond %{HTTP_HOST} ^(?:www\.)?(abc|pqr)\.com$ [NC]
RewriteRule ^blog(?:/(.*))?$ /blogs/%1/$1 [NC,L]
Please rearrange the end part of your .htaccess as
#Redirect Blogs
RewriteCond %{HTTP_HOST} ^(?:www\.)?(abc|pqr)\.com$ [NC]
RewriteRule ^blog(?:/(.*))?$ /blogs/%1/$1 [NC,L]
############################################
## rewrite everything else to index.php
## but never rewrite for existing files, directories and links
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-l
RewriteRule .* index.php [L]
Please note that the RewriteCond and the immediately following RewriteRule come together to form a redirect rule. You were putting the blog related rules right between them breaking that functionality.

Answer 2

If you have access to the vhost configuration (usually /etc/apaches/sites-enabled/abc), just enter
Alias /blog /var/www/blogs/abc
into the vhost for abc.com and analog for the vhost of pqr.com.
You also need to have mod_alias enabled. This is not possible to be done in a .htaccess file, see also this document