Do all plugins work with multisite?

In earlier days, Multisite had a separate code base, known as WordPress MU (Multiuser). Now, it’s a common code base, so the likelihood of difficulties is less. Generally, they work fine in Multisite. I’ve been using it for years, and can’t remember the last time a plugin led to this sort of issue. I tend to stick to plugins from the repository, though. A faulty plugin can potentially cause damage, though, so if at all in doubt, it makes sense to have up-to-date backups available.

Okay, good to know. I had been particularly concerned by what I read at https://premium.wpmudev.org/wpmu-manual/installing-regular-plugins-on-wpmu/ where it says, in reference to installing a plugin:

“If installing on WordPress Multisite remember that many of the regular plugins you obtain from sources other than WPMU DEV don’t work on WordPress Multisite installs and may have compatibility issues.”

And in the comment section at the bottom of the page at https://www.onextrapixel.com/2011/07/07/the-ultimate-wordpress-multi-site-network-management-guide/ there are some references to certain backup plugins not working with multisite, which also let me to wonder if it was necessary for a plugin to have explicit support for multisite.

However you’re telling me that in general most plugins should work fine with multisite, even if they don’t claim explicit support for it. If so, that’s encouraging to know! ??

It really depends on the plugin.

MOST plugins work just fine it they’re activate PER SITE.

SOME plugins won’t work if they are network activated.

If the plugin writes to DB tables and requires a lot of config, you may need to per-site activate it, but I’ve had a pretty good run of not finding more than 3 or 4 that don’t work on multisite.

Hi Ipstenu,
Can you explain what is the difference between activating a plugin per site vs. network activated?

I have no clue what the difference is, as I haven’t yet actually worked with a multisite WP installation. ??

@jeremy: Admins of individual sites (blogs) can choose to activate available plugins on their site from the site’s Plugins menu. That’s per-site activation.

If you run the Multisite installation, you can activate a plugin for every site in the network with a single click option, “Network Activate”, from the Network Admin Plugins menu. An example of that might be one which limits user access to specific plugins, https://itx.web.id/wordpress/plugin/exclude-plugins/. Individual site admins, unless they also have Super Admin rights, can’t undo that.

Ah, okay. So network activation basically forces the plugin onto all of the sites, whether they like it or not. Whereas with site activation, that would mean I (as super admin) simply install the plugin onto the server, but leave it up to each individual site admin to decide whether he wants that plugin on his site or not, and it’s up to him to turn it on. Is that right?

If so, that sounds pretty good to me, as in my case I’m only looking to create 3-4 different sites, and I’ll be the admin of most of them anyway (it’s for a small organisation where we want to have a few different team sites with their own unique themes and pages etc – but not a blog, with lots of users – just the admin and maybe 1-2 editors only).

You’ve got it. It is pretty good.

You’re really just scratching the surface of what Multisite can do, but even here you gain the advantage of a single set of user accounts which enables you to give access to any of the sites, with any role, to your users.

Whereas with site activation, that would mean I (as super admin) simply install the plugin onto the server, but leave it up to each individual site admin to decide whether he wants that plugin on his site or not, and it’s up to him to turn it on. Is that right?

Exactly.

Awesome, glad I’ve gotten my head around that! Next step is to try it out for real. Thanks for the help!

lol why not just activate them on a multi site, on a single site and on a network then see what anomalies occur…

I have a networked multisite yes I do, with sub sites as well.

I have installed over 1500 add ons and modules of these 1500 modules some 300 actually worked….
It was a case of downloading a module activation it on the network and seeing what happened…

Where some people have said that they have foreseen no problems is total rubbish……..

I have individual auctions classifieds, ecommerce, Q+A, chat, video, SEO, directory, estate agent, portfolio, Picture, forum, cv, dating, email, social, social networking, cms, chat, downloads, anon anon all interlinked and all separate sites, the network has some 50 plugins that actually work correctly….
That’s 50 out of 1200 people…

All the CSS has been done so each site or page is exactly the same as any other….. all scripts do not throw up issues of alignment etc etc it truly is a work of art…

It only took me 3 years lol…

On top of this I have interlinked VB, Joomla, SMF, we bid, dolphin, open classsifieds. Gallery 2, Opencart, Q and A, a stats script, 3 seo scripts and fully interlinked to all Google and yahoo, Facebook, twitter etc calls……….

So it is certainly not easy……..