I'm still new but I ran into this the other day. They are about to do their daily hour of downtime for maintenance.
 

Certain systems like the infamous Jita trade hub attract a larger than usual population of players.

They instituted a login queue (and this also works with an ingame version that queues traffic into and out of a busy system) to cut down on the lag.
 

Hit this a few times. Interested on the heavy details, if Nazgul or anyone else knows where I can find them.
 

It's one world made up from many "shards", you just don't notice as the gaps between shards is hidden by jump gates and the chat and "server wide" interactions are based on their own sub servers.

Read back through the older dev blogs for more information, but it's a pretty amazing infrastructure!

As for the queue, this most often happens just after DT when their re-loading all the shards it limits the number of login's over time so that the server stays stable while coming back up I presume
 

Connections can be throttled server-wide, particularly if they've been experiencing stability issues or just restarted, as Malande says.

Also though, EVE's cluster is made of three separate tiers of machines. A database cluster, a SOL cluster (where the simulations of solar systems run) and a proxy cluster, that faces the internet and your client. Even if everything is running normally, individual proxy servers can have short queues, since the load balancing system isn't perfect.

There was a presentation at Fanfest08 called "Making Mountains out of Molehills", by CCP Mindstar, which explained this and other features of EVE's server infrastructure. Naturally I can't find it on Youtube.

Most of the time, if you get a proxy-server connection queue, just close and reopen the client. You'll probably be sent to a different server, that probably won't have a queue. If it does, there's probably a global issue and patience is the order of the day.
 

A way around it is as follows:

Login.
Be told you are in a queue.
hit esc and quit the game.
Restart the game.
Login again.
Ta-da! no queue.

Malande is right, its merely a way to spread the load on the login server and the bottleneck for getting to the front is in the client's queue update rate not the speed at which the server processes the queue. Restarting the client usually gets rid of the queue.
 

BTW: despite fake reporters stating otherwise, EVE does not run all on one server. They have have multiple servers that interconnects so that users are in one universe. Instead of going the lazy way that Blizz did with WOW.
 

Actually, WoW does in fact do exactly the same thing in putting each continent on a different server. That's why you get a loading screen going from Northrend to Outland to Kalimdor to Eastern Kingdoms to an instance. It's just that they can't put everyone on one server, because, let's be honest, there are pretty much no computers that could handle every 80 on every server in one Dalaran, to give the most extreme example.
 

The game is lying. Close it and start it again.
 

There are capacity constraints in EVE. You may see a login queue. There can also be gate delays as you jump from one shard to another.

And one hour of scheduled daily downtime, which is why you see the phrase "working 23/7" in posts.

CCP is wonderfully, refreshingly open, at least for a no longer tiny company; you can see exactly how many are on and what the maximum was.

Currently,
http://eve-offline.net/?server=tranquility
shows 49,626 online with today's max being 49,626 and record being 56,817
 

One of the little lies in the Eve game is that all that “space” is used. In fact a relatively small number of systems are massively used and the bulk are ignored. A few years ago before they ripped out a bunch of the inter-system gates this queue had gotten real bad. It was not unusual at all to wait for quite some time if you happened to be logging into a busy system.

Anyway, as has been said, Eve does not run on one physical piece of equipment. Like all other games of this type it runs on an array of physical machines. Due to the very small player base of Eve they can afford to cross connect all the servers into a single virtual world. If this game ever gained the sort of population the big boys have they’d most certainly have to open another western server. They already run a second virtual world space in asia.
 

I would run into the same thing when I played EVE. I had two accounts and sometimes one would get the message and then the second would log in fine. Mandrill is correct. Close out EVE and try logging in again and it should be fine.

At the time I was still active on EVE, there were some posts that effectively said it was not a problem in the playing server but a problem in the login server, which is why closing and trying again worked: You end up changing login servers. I can't guarantee that this is true, but I do know that I would have to use the close and login again trick when the total population of pilots was fairly low sometimes.