still get error after that I have cleaned the port which causes the error

[Ryan Schmidt]

On Sep 18, 2015, at 10:31 AM, 心如烛光 wrote:

>     I failure to install opam for my macbook(osx 10.8.5 mountain lion)with macport. Even after that I have cleaned the re2c which leads to the error and reinstall opam again,the error still exists.What makes the installation fail?And how could I fix it?
> here is the terminal's message and the log of the port:
> The terminal:
> $  sudo port clean re2c
> --->  Cleaning re2c
> $ sudo port install opam
> --->  Computing dependencies for opam
> --->  Dependencies to be installed: aspcud gringo re2c scons
> --->  Fetching archive for re2c
> Warning: Your DNS servers incorrectly claim to know the address of nonexistent hosts. This may cause checksum mismatches for some ports. See this page for more information: <https://trac.macports.org/wiki/MisbehavingServers>
> --->  Attempting to fetch re2c-0.14.3_0.darwin_12.x86_64.tbz2 from http://jog.id.packages.macports.org/macports/packages/re2c
> --->  Attempting to fetch re2c-0.14.3_0.darwin_12.x86_64.tbz2 from http://packages.macports.org/re2c
> --->  Attempting to fetch re2c-0.14.3_0.darwin_12.x86_64.tbz2 from http://mse.uk.packages.macports.org/sites/packages.macports.org/re2c
>       [                                    ]   0.0 %        speed: 0 B/s        --->  Fetching distfiles for re2c
> --->  Attempting to fetch re2c-0.14.3.tar.gz from http://aarnet.dl.sourceforge.net/re2c
> --->  Verifying checksums for re2c
> Error: Checksum (rmd160) mismatch for re2c-0.14.3.tar.gz
> Error: Checksum (sha256) mismatch for re2c-0.14.3.tar.gz
> ***
> The non-matching file appears to be HTML. See this page for possible reasons
> for the checksum mismatch:
> <https://trac.macports.org/wiki/MisbehavingServers>
> ***

The problem occurred because of the following two issues:

1. The port you were trying to download does not have a binary and one of the servers on which the source code was thought to be found no longer exists.
2. Your computer is configured to use DNS servers that are misconfigured as explained in https://trac.macports.org/wiki/MisbehavingServers

I have fixed the first problem by updating the list of SourceForge mirrors in https://trac.macports.org/changeset/140417.

If you want to avoid similar problems in the future, you should ask whoever runs the DNS servers you are using to fix their servers so that they return the "unknown host" response when asked about an unknown host. Or configure your computer to use different DNS servers that already work correctly. For example, you could use Google's public DNS servers: https://developers.google.com/speed/public-dns/