Netsplit facts for kids

In computer networking, especially on chat systems like Internet Relay Chat (IRC), a netsplit happens when two servers suddenly disconnect from each other. Think of it like a big online chat room that's made up of many smaller rooms connected together. If the connection between two of these smaller rooms breaks, the whole chat network gets split into two parts.

When a netsplit happens, it looks like all the people who were on the other side of the broken connection have suddenly left the chat. But they haven't really left; they just can't see or talk to you because the connection is down!

A normally working network: Bob, Joe, and Sara can all see and chat with each other.

A network during a netsplit: Bob sees Joe leave, and Joe sees Sara and Bob leave.

What a Netsplit Looks Like

When a netsplit happens, you'll often see many users suddenly "quit" from the chat. Then, when the servers connect again, you'll see all those users "rejoin." It can be a bit confusing!

A typical netsplit shown in an IRC chat program.

Here's an example of what you might see on your screen during a netsplit:

On a chat program with a graphical interface (GUI)

* usera has quit (a.irc.net b.irc.net)
* userb has quit (a.irc.net b.irc.net)
* userc has quit (a.irc.net b.irc.net)
* usera has joined #channel
* userb has joined #channel
* userc has joined #channel

This shows that 'usera', 'userb', and 'userc' appeared to leave the chat. Then, they all "joined" back when the connection was fixed.

On a command-line chat program like irssi

00:00 -!- Netsplit a.irc.net <-> b.irc.net quits: usera, userb, userc
00:00 -!- Netsplit over, joins: usera, userb, userc

This message directly tells you that a netsplit happened between two servers (a.irc.net and b.irc.net) and lists the users who seemed to quit. Then, it announces when the netsplit is over and the users rejoin.

On a private network

* usera has quit (*.net *.split)
* userb has quit (*.net *.split)
* userc has quit (*.net *.split)
* usera has joined #channel
* userb has joined #channel
* userc has joined #channel

This is similar to the GUI example, but it uses general terms like "*.net" and "*.split" to show that the split happened somewhere on the network.

Images for kids

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  A netsplit on freenode, shown in the HexChat IRC client.

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  A netburst on freenode, shown in the HexChat IRC client.

See also

In Spanish: Netsplit para niños