yhdev/dat/ncdc-faq

=head1 About ncdc


=head2 What about other text-mode clients?

L<microdc2|http://corsair626.no-ip.org/microdc/> - A rather nice client, yet
not exactly there. It's limited to connecting to a single hub, hasn't been
updated since 2006, and the readline interface is slightly awkward to use.

L<nanodc|http://sourceforge.net/projects/nanodc/> - Can't comment much on this,
except maybe that rocket science is perhaps easier than getting nanodc to
compile.

LDCC - Uses DCTC as backend and an interface based on TurboVision. All
mentioned projects are dead: neither LDCC, DCTC nor TurboVision are seeing any
recent development.

L<ShakesPeer|http://shakespeer.bzero.se/> - Appears to have a commandline
interface as well. I haven't personally tried it, but have not heard many
positive things about it.  Has not seen any recent development, either.


=head2 Why did you start from scratch? Why not use the DC++ core?

There are many reasons why I chose not to use code from existing projects, but
all of them boil down to the following two: 1) I am a control freak, and 2)
personal preferences. That is the short answer. The long answer will require a
full article, and I don't feel like writing that much at this point. >_>


=head2 What protocol features does ncdc support?

For ADC: BASE, RF, TIGR, BZIP, ADCS, KEYP and SUDP.

For NMDC: NoGetINFO, NoHello, UserIP2, MiniSlots, XmlBZList, ADCGet, TTHL and TTHF.

ncdc also support TLS-enabled connections for both hub connections and
client-to-client connections on both ADC and NMDC protocols. Note that ncdc
does not support some of the older NMDC protocol features, like $Get,
$GetZBlock, $CHUNK, $Cancel or non-XML file lists. I am not aware of an other
up-to-date client that still uses any of these features.




=head1 Troubleshooting

=head2 This "Generating certificates..." is taking ages!

When starting up ncdc for the first time, it will need to generate a TLS
certificate. If you're on Linux, GnuTLS will use C</dev/random> to obtain
random bytes. Unfortunately, this can be horribly slow, and in extreme cases it
may take up to an hour before the certificate has been generated. GnuTLS does
not provide a way to use a faster but less secure alternative, so here are some
tips to speed it up or cheat a little.

B<Speed it up:> If you're on a desktop, the general advise is to do something
else on the background so that Linux can generate more data. For example, move
your mouse around a bit, go do some web surfing or play a game. Any activity
might help.  If you're on a server, you could start transferring some large
data over the network.

B<Cheat:> There is also another way to "generate" randomness without waiting
for too long: You can feed some bytes from C</dev/urandom> back to the system
by running the following command as root: C<dd if=/dev/urandom of=/dev/random
bs=512 count=1>.  You might have to run that command multiple times to complete
the certificate generation, but certainly no more than about 5 times or so.
Note that this solution weakens the security of the certificate by a bit. For
ncdc that doesn't matter at all, but if you have other applications reading
from C</dev/random>, then the security of those applications is also affected.
Unless you happen to be running something that absolutely requires ulta-secure
random numbers, this trick should be perfectly fine.


=head2 Ncdc crashes a lot!

Since version 1.10, it shouldn't crash at all. Please report a bug. (If you're
running an older version, please upgrade!)


=head2 Ncdc uses too much disk space!

First, look where this disk space goes to (hint: use
L<ncdu|http://dev.yorhel.nl/ncdu>). If it's the log files: you can safely
delete or rotate them (see next question).

The I<db.sqlite3> file can also grow quite large in certain situations. If you
modify or rename a lot of files in your share and ncdc re-hashes them, the old
hash data associated with the files is not removed from the database, resulting
in wasted disk space. The C</gc> command in ncdc can be used to clean up this
unused data. Be warned, however, that this command needs roughly twice the size
of the old db.sqlite3 file for temporary storage, so make sure you have enough
space available. (Note that this behaviour is not specific to ncdc, most other
DC clients do the same.)


=head2 Why doesn't ncdc rotate log files automatically?

Because you can easily do that yourself. You can either use logrotate or a
simple script that runs from a cron. For an example of the latter option,
L<this is the script I use|http://p.blicky.net/s7132>, which is run as a
monthly cron job.



=head1 Can ncdc...


=head2 Can ncdc use the hash data or configuration from an existing DC++ installation?

No, ncdc uses its own configuration and hash storage directory.  However, on
popular demand I could write a conversion utility to transfer the hash data
from other clients to ncdc's format.


=head2 Can ncdc run in the background / as a daemon?

As with most ncurses applications: no. At least, it does not have this
functionality built-in. Ncdc is designed to be used in combination with a
separate terminal multiplexer or detach utility to handle this. Have a look at
L<GNU screen|http://www.gnu.org/s/screen/>,
L<tmux|http://tmux.sourceforge.net/> or L<dtach|http://dtach.sourceforge.net/>.


=head2 Does ncdc support UPnP?

Not natively. However, it is possible to use L<this
script|http://www.howtoforge.com/administrating-your-gateway-device-via-upnp>
and manually keep a port open using a cron job. I have no experience with this
myself, though. I just run ncdc directly on my router. :-)


=head2 Are there any programs available for analyzing the transfers.log file?

Nothing like that is included in the release yet, but there is a simple Perl
script available: L<ncdc-transfer-stats|http://p.blicky.net/agolr>, and a short
Go program: L<ncdc-share-report|http://p.blicky.net/h25z8>.