###### always access from www and redirect multiple doamins to one

rewriteCond %{http_host} ^domain\.com$ [OR]
rewriteCond %{http_host} ^domain\.org$ [OR]
rewriteCond %{http_host} ^www\.domain\.org$ [OR]
rewriteCond %{http_host} ^subdomain\.domain\.org$ [OR]
rewriteCond %{http_host} ^www\.subdomain\.domain\.org$ [NC]
rewriteRule ^(.*)$ http://www.domain.com/$1 [r=301,L]

######always access from non-www and redirect multiple doamins to one

rewriteCond %{http_host} ^www\.domain\.com$ [NC]
rewriteRule ^(.*)$ http://domain.com/$1 [r=301,L]

.htaccess domain redirects

unix, htaccess

Bash