[RESOLVED] LAC exits with "UNABLE TO RESOLVE HOST NAME"

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When attempting to access an online mission, LAC sometimes exits with the following message:

   UNABLE TO RESOLVE HOST NAME.
   THIS MEANS YOU HAVE NO INTERNET ACCESS, OR ELSE YOUR
   DNS SERVER IS TEMPORARILY DOWN. IF YOUR COMPUTER CANNOT
   GET INTERNET ACCESS, NONE OF LAC'S ONLINE MISSIONS
   WILL WORK AND LAC MAY EXIT IF YOU ATTEMPT TO START ANY
   OF THOSE ONLINE MISSIONS.

If the user has installed espeak tp help LAC verbalize text, the user also hears this text verbalized:

   LAC IS UNABLE TO RESOLVE THE HOST NAME. 
   THIS MEANS YOU HAVE NO INTERNET ACCESS 
   OR ELSE YOUR DNS SERVER IS TEMPORARILY 
   DOWN. NONE OF LAC'S ONLINE MISSIONS 
   WILL WORK.

Until version 9.76, that error message was only seen in appropriate situations, and the guidance it offered was accurate.

However, LAC version 9.76 ("Lac09p76") has a new bug that can cause this error EVERY time you attempt to start an online mission. Version 9.76 implements a new approach for finding the LAC server, and it changed the default data in the LacConfig.txt file to do so. When LAC version 9.76 finds the default values that it expects to find in LacConfig.txt, this error never occurs.

However, when LAC version 9.76 finds DNS-related values in the LacConfig.txt file that were acceptable in prior versions but that do NOT match its new expectations, the error seen above is triggered every time the player launches any of our online missions.

Consequently, users that are UPGRADING to version 9.76 from a prior version are likely to suffer from this error.

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Fortunately, we've found two easy ways to work around this problem with version Lac09p76 as follows:

1 of 2: Delete your ~home/.LAC/LacConfig.txt file. LAC will automatically rebuild it using default values that won't trigger the problem. Of course, after restarting LAC it will run in a "generic" window with "generic" CommunityHandle, etc. You will want to resize your preferred video display size, favorite airplane, graphic detail settings, etc. All of these settings are easily accessible through LAC's prominent menus, so this option is very easy unless you've done a LOT of customizing.

or

2 of 2: This approach will preserve any customization you've made to your graphic resolution, graphic detail, sound volume, realism, DefaultAircraft, CommunityHandle, etc.
Edit your ~home/.LAC/LacConfig.txt file with a simple text editor. Change the area that defines Internet Access to the LAC Server so it looks like THIS:

# If you are going to use LINUX AIR COMBAT on a network, you must configure the IP address
# of a Linux Air Combat Server or of one other computer also using LINUX AIR COMBAT. To do
# this using a numeric IP address like 192.34.59.172, you must enter four numbers into the
# next four Configuration Lines. For Example, if you want your computer to connect with
# another local LAC user for 2-player Head to Head activities or to another LAC server that
# is on your local LAN using IP address 192.168.1.2, you would enter 192 on the first of the
# next four lines, after ServerIpByte1of4 =.  Then you would enter 168 on the second of 
# those lines, 1 on the third line, and 2 at the end of the fourth line, after it says
# ServerIpByte4of4.

 ServerIpByte1of4 = 192
 ServerIpByte2of4 = 34
 ServerIpByte3of4 = 59
 ServerIpByte4of4 = 172

# You can use the four lines above to specify any numeric IP4 address, referencing any
# computer on the worldwide Internet. Since 2020, LAC's server has normally been hosted at IP
# address 192.34.59.172, so you could use those values. However, because that numeric IP
# addresses may change someday, it's generally best to also configure LAC's Domain Name as
# an additional way to locate our server. That's done through the next 3 configuration
# lines. If you configure those lines as usual, then the numeric IP address listed above
# gets replaced through a Domain Name System (DNS) lookup instead.

# Note that the monthly cost of hosting the LAC Server at LinuxAirCombat.com is paid by
# the good people at AskMisterWizard.com and is derived from advertising revenue resulting
# from traffic to their web site. If they ever decide to cease this funding, the LAC server
# may disappear. In that case, you will always be able to enter the numeric IP address of
# some other player above and enjoy LAC's two-player Head-To-Head mode with him or her.

# Of course, because LAC's source code is published, it is also possible that somebody else
# may start hosting a LAC server through some other IP address. In that case, you could use
# that LAC server by entering its numeric IP address into the four configuration lines
# above.

# Most people reference their preferred LAC server through a Domain Name Service (DNS)
# name instead. To do that, use the next three Configuration Lines to specify the
# remote network peer DNS Address, expressed as three separate words. For example,
# If you know that your peer (or some other LAC server) has configured his computer
# behind a NAT Router and has set up port forwarding and dynamic DNS according to industry
# norms with DNS address bigshot33.my-ip.biz then you would enter bigshot33 in the first
# Configuration Line below, you would enter my-ip in the second line below, and you
# enter biz in the third line below. Alternatively, if you need to use the numeric IP
# from the prior four configuration lines instead, you should enter void into all three
# lines below. (When LAC sees the keyword    void    in those lines, it knows that you
# want to use the numeric IP address instead of DNS.)

# First of 3 sections of network peer DNS name (defaults to our server at LacServer2) :
 RemoteDnsIpAddressHost
void
# Second of 3 sections of network peer DNS name (defaults to our server at LinuxAirCombat) :
 RemoteDnsIpAddressSecondLevelDomain
void
# Third of 3 sections of network peer DNS name (defaults to our server at com) :
 RemoteDnsIpAddressTopLevelDomain
void

When editing that area of your old LacConfig.txt file, you'll find that it's almost identical with the example above. You don't need to change any of the lines commencing with "# " because those lines are just comments.

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This bug is fixed in Version Lac09p77, available for beta testing as of 17Oct2024.