Gammon Forum

Troubleshooting problems connecting to your favourite MUD / MMORPG

Are you having trouble connecting to your MUD? Before you post a message on the forum about a "client bug" - read the posting below. It will help you understand the various steps involved in connecting to a multiplayer game, and how to interpret various sorts of error messages.

First, a network diagram, to illustrate the path that a network connection is likely to take:

Let's take each step at a time ...

Resolve the Domain Name

One of the first things your client has to do is "resolve the domain name". What this means is that an alphabetic name (like smaug.org) has to be converted to a network address (like 216.251.47.10). Packets that travel over the network are addressed by number (eg. 216.251.47.10) not by name. The use of domain names is a convenience for humans.

To convert a name, the client has to contact a Domain Name Server (DNS), sending it the name it wants resolved. If possible the server replies with the name converted into a number.

You can see from the network diagram above that the Domain Name Server (DNS) is number 6 on the list of steps, so there are quite a few things that can go wrong before the domain name is resolved.

Firewall (item 2 on network diagram)

Many PCs these days have a firewall installed by default, or you may have chosen to install one yourself, or upgrade the existing one. Attempting to use your client, for the first time, to access the Internet (including the DNS) may result in a warning dialog box like this (the IP address will be different):

It is important to click "Allow" and preferably "Save the answer as a permanent rule", otherwise you will not get much further using your client to access the Internet. If you don't see a dialog box then it is possible you (or someone else) denied access previously, and it has been saved as a rule in the firewall already. If this happens you will probably see a message like this in MUSHclient:

Unable to connect to "Realms of Despair", code = 10051 (Network is unreachable)

The message "Network is unreachable" suggests that the firewall has denied access to the network to this program. In this case you would need to go into your firewall configuration, find the relevant rule, and modify it:

I notice that MUSHclient has been blocked by someone, so I click on Edit to modify the rule:

Change the rule to Allow, and click OK to save and OK again to save the changes to the firewall rules. Your firewall may be different but the same general principles will apply.

Router / modem (item 3 on network diagram)

The next link on our chain is the home router / modem (or cable modem) which connects our PC to the Internet. Personally I have two boxes, one is the modem supplied by the cable company, and the other is a home router, which lets me share the Internet connection between multiple PCs. Sometimes I find that these devices fail, and powering them off and back on can help restore a lost connection. If I turn off my router, and try to connect I get this error message:

Unable to connect to "Realms of Despair", code = 10060 (Connection timed out)

Notice the different message compared to the firewall problem. This time it timed out (that is, got no response) while trying to connect.

A further possible problem is that routers often have their own firewalls. You may need to configure the firewall to allow outwards access from your PC to the MUD. However it is unlikely your router will not allow you to access your DNS server, otherwise you would not get much network browsing done at all.

If you have a dial-up connection, you may quite likely not have a router, but only a modem, in which case we move onto the next step ...

The next item to check is your modem, whether it be a cable modem, ADSL modem, dial-up modem, or some other device. If it is a dial-up modem, check it is connected. Reconnecting, or powering the modem off and on again can be helpful. The symptoms of a problem with the modem are:

• Cannot connect to any sites on the Internet at all (eg. in your web browser)
• Cannot send or collect mail
• Still able to connect to other PCs on the home network (if any)

Internet Service Provider (ISP) - (item 4 on network diagram)

The next step in the network diagram is your ISP. This is your gateway to the "main" internet from your home / office / school. Potential problems with the ISP are:

• Account not paid (so they suspended your access)
• Allocated time up for today (eg. you used up your 2 hours' allowance).

Internet Service Provider Firewall - (item 5 on network diagram)

ISPs can also have their own firewalls. In the case of businesses or schools these may well be configured to stop employees / students playing network games. Symptoms of this are:

• You can browse the Internet with your web browser
• You can send and receive mail
• You cannot connect to your favourite MUD / MMORPG.

In this case there probably isn't much you can do - attempting to ask your boss to let you play a MUD while you are supposed to be working may not be a smart career move.

Domain Name Server (DNS) - (item 6 on network diagram)

Finally we should be ready to resolve the domain name - that is, convert "smaug.org" to "216.251.47.10" or whatever number it is. It is possible for DNS servers to go down, they are a PC like anything else, however generally speaking people who provide DNS servers provide backups (so you should see a list of DNS server addresses in your network configuration). However if you have misspelt the domain name you are likely to see an error message like this:

Unable to resolve host name for "smaugg.org", code = 11001 (Host not found)

Notice the misspelling of smaug.org, resulting in a message that it cannot "resolve host name". If you get this message you may want to check your spelling, and check that the domain name still exists. For a really old game it is possible the name has been allowed to expire.

If we successfully resolve the domain name, you should be able to see the resolved IP address in MUSHclient, like this:

Notice the number 216.251.47.10 in that dialog box. That shows we have successfully resolved the domain name. Now to actually connect to the world ...

Connect to the game

Now that we have a domain name resolved we can move onto actually connecting to our game. In the case of MUSHclient it caches the IP address, so that if you disconnect from the game, and then reconnect (without closing MUSHclient) it bypasses the step of getting the domain name resolved and uses the cached IP address.

Many of the steps described above also apply to actually connecting to the game, except we will be contacting a different "port" number (the game port) and a different IP address (the game IP address rather than the domain name server IP address). These differences may make the various firewalls described earlier react differently.

MUD game router - (item 8 on network diagram)

The next hurdle for our connection attempt is to get past the router at the game server end. If you are just setting up a new game you may need to read up on Port Forwarding. One site to look at is http://www.portforward.com/ - this has information about configuring routers to port-forward. Normally players of games don't need to concern themselves with this, however if you are trying to get a server to work, you should pay attention to the detail there.

MUD game firewall - (item 9 on network diagram)

A further hurdle, if you are setting up your own game, is to configure your PC (or Linux) firewall to allow incoming connections to your game. The default may well be to refuse them.

Game server - (item 10 on network diagram)

Finally we have reached the game server - but is it up? Servers (and PCs) crash. If everything else looks OK but you get a message like this:

Unable to connect to "Realms of Despair", code = 10061 (Connection refused)

This could simply mean the MUD has gone down and is being rebooted. One thing to try is MUD Connector which, amongst other things, allows you to check if the MUD is up. If it is down, there isn't much you can do except patiently wait for the admins to fix the problem.

1. Can you browse web sites?
   
   The first thing I do is switch to my web browser and try to contact some web site that has dynamic content (such as this forum). It is important to choose a forum, blog, or similar site which has to be refreshed every time you view it, or your web browser may simply display a cached version of a page fetched previously. Seeing a cached page doesn't prove much about your Internet connection.
   
   If you can see my forum, this shows:
   
   
   
   • The PC network interface is working and plugged in
     
   • The router is working
     
   • The (cable) modem is working
     
   • The ISP is working and not having technical difficulties
     
   • You can reach your domain name server (DNS) because it had to resolve the web site name into an IP address
     
   
   
   If browsing the web using a web browser works, go to Step 2, below.
   
   If you cannot browse the web, then you have serious problems. In fact you won't be able to read this page unless you have printed it out in advance. ;)
   
   Check your:
   
   
   
   • PC network interface (eg. did someone unplug the network cable?)
     
   • Router
     
   • Modem
     
   • Is the modem still connected (eg. has a dial-up connection dropped out?)
     
   • If possible see if your ISP has announced technical problems. This is hard to do if you cannot use the Internet, but you could ring their help desk, or ring a friend and ask if they too are having problems.
     
   
   
   One thing to try is to "power cycle" (turn off, wait, and turn on again) all the relevant gadgets you have control over. I would start with the one furthest from the PC and work backwards. That is:
   
   
   
   • The modem
     
   • The router
     
   • The PC itself
     
   
   
   Doing this can clear transient problems that have occurred.
   
   

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2. Have you been able to connect to this game recently from this PC?
   
   If you have recently been playing this game (like, yesterday, or five minutes ago), then probably there is not an issue with router or firewall configuration. In this case, go to Step 3, below.
   
   However if you have never connected to this game from this PC, the problem may well be someone has set up a firewall or router configuration blocking online game access.
   
   This is particularly likely if you are at a school, college, or workplace. They may configure their router to let certain "ports" (like 80 for web browsing) go through, but block other ones.
   
   If you have never connected from this PC, first establish if the game is still up. If you played it an hour ago at home, then went to school, and now can't reach it, then probably there is a firewall issue. This may be impossible to resolve, and you may have to wait until you are back at home again.
   
   As suggested earlier, you could go to http://www.mudconnect.com/ and see if the game is currently up.
   
   
   

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3. I was playing the game five minutes ago and now I can't.
   
   
   If you have got down to Step 3: you were playing the game recently, and now you can't, however you can still browse the Internet, get mail, etc., then probably the game itself is down.
   
   This could be because:
   
   
   
   • The game simply crashed and is being rebooted - in which case it will be back shortly.
     
     
   • The game crashed, and is awaiting an admin to come and reboot it - in which case it may not be back for hours.
     
     
   • The game server had a hard disk crash - this may mean it will be down for days while they find another server and restore from backups (if any).
     
     
   • The game has been brought down permanently. Perhaps the admins got tired of running it, or couldn't pay the bill for the game server.
     
     
   • There has been a Denial of Service attack on the game server, or the nearby ISPs. This may result in the game being down until it can be resolved.
     
     
   • The game has been deliberately brought down for an hour for maintenance or backups.
     
     
   • The game has been deliberately brought down to install new features.
     
     
   • The game server has had to move to a new ISP (service provider) and this is taking a few days to do.
     
     
   • The game is still up, but you have been booted and banned for some in-game behaviour. If you find that you cannot connect a couple of minutes after insulting one of the admins, this may well be the case.
     
     
   
   
   Steps I would take to work out what is happening would be:
   
   
   
   • Wait half an hour, and then try to connect again.
     
     
   • Go to the game's web site. There may be an announcement, especially if there is expected to be a lengthy outage due to a crash, maintenance, site move, or installation of new features.
     
     
   • If the game runs a forum site, try that. Often forums are updated more quickly than "official" announcements.
     
     
   • Go to http://www.mudconnect.com/ and see if the game seems to be up using their "test game" feature.
     
     
   • Contact other players, if you know their phone numbers or email addresses. If another player says "I am still playing" that shows that the game is still up.
     
     
   • Check your email for a message from the game admins about the game going down for a while, or your character being banned.
     
   
   
   

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4. I keep getting disconnected
   
   Some routers have an "inactivity timeout" period set. This may be 5 minutes or so. Symptoms are that you get disconnected after playing for a while, but you can reconnect OK.
   
   Try:
   
   
   
   • Configuring the router to disable "inactivity timeouts".
     
     
   • Install the "Config_Option_Changer" plugin which ships with MUSHclient (Config_Option_Changer.xml). Then use that to set the option "Send keep-alives" to "Yes". Then restart the client. This sends a special "keep-alive" packet every 2 minutes, which should tell the router to not disconnect you.
     
     
   • If that fails, try using a timer to send a non-intrusive command (like "look") to the MUD every couple of minutes.
     
   
   
   

netstat -a

netstat -ab

Active Connections

  Proto  Local Address          Foreign Address        State           PID

  TCP    localhost:4000         localhost:0            LISTENING       2224
  [smaug.exe]

  TCP    localhost:3843         localhost:3844         ESTABLISHED     2896
  [firefox.exe]

  TCP    localhost:1066         10.0.0.2:4020          ESTABLISHED     3076
  [MUSHclient.exe]

• Smaug server is listening for connections on local port 4000
  
• Firefox has an established connection on port 3844
  
• MUSHclient has a connection to another of my MUD servers on 10.0.0.2