How to manage the network admin panel in WordPress multisite
Every site in a WordPress multisite network has its own admin panel. These admin panels are the same as those of regular singe-site installations. In addition to this there's a network admin panel which has options and functions that are not available in the admin panels of individual sites.
To access the network admin panel you can log in as a super admin/network admin to the admin panel of any of the sites in the network and then go to My Sites menu in the upper left corner>Network Admin>Dashboard. Alternatively, you can open directly the network admin panel login page by using its URL address. If the URL of the main site is yourdomain.com, the URL of the network admin panel will be yourdomain.com/wp-admin/network. On the left side of the network admin panel there are several menus each opening the corresponding section.
Clicking on the Sites menu will display a page with a table that lists the sites in the multisite network. To add a new site click on one of the two Add New buttons, on the following page specify the URL of the site, the site title and admin email in the respective fields and click on the Add Site button.
If you hover the mouse pointer over a row in the table that lists the existing sites, several buttons will appear. Using the respective button you can remove the site, you can go to its dashboard or its frontend. Clicking on the Edit button will open a page with some settings related to the site. At the top of the page there are a few tabs: Info, Users, Themes, Settings. Each displays a page with a bunch of settings.
Click on the Users menu on the left to manage the users for all the sites in the network. All the registered users regardless of the site(s) in the network with which they are associated will be shown in a table. You can delete and edit the profiles of the users.
One thing that makes this section different than the same section of admin panels of individual sites is that you cannot change the user role of an existing user. For this purpose you have to edit the user profile from the admin panel of the particular site.
If you add a new user from the Users section of the network admin panel, the user will be added to all sites in the network and the user role will be set automatically to subscriber for all the sites. Note that if you add a user in such a way that user will not be listed in the Users section of the admin panels of individual sites.
Click on the Themes menu on the left to install and manage themes. In a multisite network you can install themes only from the network admin panel; it cannot be done from the admin panels of the sites. After you install a theme you can either network enable it or network disable it. If you network enable a theme, then it will be listed in the Themes sections of the admin panels of all sites in the network. From each admin panel it can be activated and made the current theme for that site.
You can also enable a theme only for a particular site(s). To do this, in the network admin panel go to the Sites section, then click on the Edit button for the particular site, after that click on the Themes tab at the top of the page that opens and enable the theme.
If you edit the files of a theme, the changes will be visible on all sites that use the theme. To avoid this we recommend that you create a separate child theme for each site for which you want the theme to be enabled.
From the Plugins section of the network admin panel you can install, remove, activate and deactivate plugins. Plugins in a multisite network can be installed only from the network admin panel. Then if you network activate a plugin it will be used by all sites in the network and it will not be shown in the Plugins section of the admin panels of individual sites. This means that a network activated plugin can only be deactivated from the network admin panel. Those plugins that are deactivated will be listed in the Plugins section of the admin panel of each site in the network and they can be activated on a per site level. By default, this can be done only by super admins. If you want to allow admins of individual sites to access the Plugins section of the admin panel of their site and active/deactivate plugins, go to Settings menu>Network Settings in the network admin panel, and on the page that opens find the section Menu Settings, mark the checkbox Plugins and click on the Save Changes button.
If you go to Settings menu>Network Settings in the network admin panel this will display a page with a lot of settings for configuring various aspects of your network. For more information check out the article on how to configure and manage the network settings in WordPress multisite or the more detailed tutorial on how to manage the network settings in WordPress multisite.
Posts, Pages, Categories, Tags
These cannot be managed from the network admin panel and it doesn't contain any settings related to that. Posts, pages, categories and tags can be managed only on a per site level from the admin panel of each site in the network.
There are no settings related to permalinks in the network admin panel but there are a few things to consider.
If you use pretty permalinks and the multisite network is configured to use subdirectories for the sites in the network, the path /blog is automatically inserted in the post URLs of the main site (e.g. yourdomain.com/blog/post-title instead of yourdomain.com/post-title). The post URLs of other sites in the network are not affected. The URLs of static pages of the main site are not changed either.
If your multisite network is configured to add the sites as subdirectories and you add a site with a path that's the same as the slug of a static page on the main site, then the page will not be accessible any more. For example, if you have a page with the URL yourdomain.com/example and you add a site in the network with the URL yourdomain.com/example, then the site URL will overwrite that of the page.
From the Updates section of the network admin panel you can upgrade the whole WordPress application and the installed themes and plugins. This can't be performed from the admin panels of individual sites in the multisite network.
When there's a new WordPress version you'll be informed with a message that's shown at the top of the network admin panel and at the top of the admin panel of each site in the network. To perform the upgrade go to Updates menu>Available Updates sub-menu and click on the Update Now button. After that update is complete go to Updates menu>Upgrade Network sub-menu and on the page that opens click on the Upgrade Network button to update the database and finish the upgrade.
If there's a new version of any of the themes or plugins that you've installed you can perform the upgrade from Updates menu>Available Updates sub-menu in the network admin panel. Just mark the checkbox for the respective theme/plugin and click on the Update Themes or Update Plugins button (depending on whether you want to update a theme or a plugin).
For more information and screenshots you can also check out the tutorial on how to manage a network in WordPress multisite.
Other WordPress multisite tutorials that you may find useful: