WordPress Network Setup 3.5.1 Multisite Requirements

Here is a digest version of WordPress Network (multisite) setup for multiple domains. In WordPress 3.5.1, there were two network multisite setup modes: subdomain and subfolder domains. We focus here on the subdomain mode of supporting multiple domains. Offered are opinions on setup differences between network subfolder and subdomains modes, setup preparation, and setup requirements.
* tld below means top level domain, ie. .com .net .org

SubDomain network requirements:
-your site must be accessible as domain.tld and not www.domain.tld unless,
you plan on something like subdom.www.domain.tld
see your DNS A record for @, and possible URL Rewrite rules
-site must run from web docroot, but can be installed in a subfolder
-see “Run WP from docroot when not installed in docroot” here

Flip Network (multisite) Mode to Single Mode:
- edit wp-config.php to revert to single mode
- near bottom, comment line: define(‘WP_ALLOW_MULTISITE’, false);

Enable Network (multisite) Mode:
- edit wp-config.php to enable multisite
near bottom, add or remove commenting of the line “define(‘WP_ALLOW_MULTISITE’, true);”
- log off/on, now have Tools -> Network Setup (if not previously configured)

Install Network
- if you plan to use sub-domain network:
- Settings->General->Site Address to domain.tld ie. not www.domain.tld
- disable all plugins
- then Dashboard -> Tools -> Network Setup (if not previously configured)
- chose type of network addresses you’d like to see for your sites
-subdomain sites (ie. child.domain.com) or,
-subfolder sites (ie. domain.com/child)
- wildcard * dns is preferred by WordPress, but is incompatible with most shared hosting
-dns A or CNAME records for subdomains will have to be manually created
- setup displays lines to be added to wp-config.php to enable the network
- setup also displays .htaccess or web.config settings required
- backup the mentioned files before editing them
- we recommend ‘network activating’ only Child themes, unless just taking a test drive
- themes, plugins have to first be ‘network activated’ from your Network Dashboard
- while we’re at it update permalinks
- IIS pretty permalinks requirements:
- iis url rewrite module 2 installed
- web.config in docroot (see install network setup for web.config contents)

Admin Dashboard Links broken after Network setup
- hack:    edit wp-includes/link-template.php func network_admin_url()
$url = network_site_url(‘yourfolder/wp-admin/network/’, $scheme);