Re: need to disable IPv6

[Ignatios Souvatzis <ignatios%cs.uni-bonn.de@localhost>]

On Thu, Jun 28, 2012 at 04:58:16PM +0900, Takahiro Kambe wrote:
> In message 
> <CAK9rGbZ=BZr=f6XtNVUUWu4U11Uok0URsCoMaf8-T8jTb=Okzg%mail.gmail.com@localhost>
>       on Thu, 28 Jun 2012 11:50:46 +0300,
>       Aleksey Cheusov <cheusov%tut.by@localhost> wrote:
> > On Thu, Jun 28, 2012 at 10:48 AM, Takahiro Kambe 
> > <taca%back-street.net@localhost> wrote:
> >> What is your case?
> > 
> > The following is sent to stderr both with and without -V.
> > 
> > Trying 2001:470:1f05:3d::21:21 ...
> > ftp: Can't connect to `2001:470:1f05:3d::21:21': No route to host
> Then, ftp(1) should be fallback to IPv4, but it seems to not.
> I don't have any idea why it is, at least without knowning your
> Internet connection environment.

I checked experimentally. I've deleted the v6 default route:

# route delete -inet6 default
delete net default
# netstat -rnf inet6 | grep default
# ftp -V ftp.netbsd.org
ftp: Can't connect to `2001:470:1f05:3d::21:21': No route to host
Name (ftp.netbsd.org:ignatios): ftp
Password: 
ftp> [1] + Suspended               ftp -V ftp.netbsd.org
# netstat -nf inet | grep '21 '
tcp        0      0  131.220.4.131.61938    199.233.217.249.21     ESTABLISHED
# 


bs -l
[1] + 9204 Suspended          ftp -V ftp.netbsd.org
# fstat -p 9204
USER     CMD          PID   FD MOUNT       INUM MODE         SZ|DV R/W
...
root     ftp         9204    5* internet stream tcp 199.233.217.249:21 <-> 
131.220.4.131:61938

so it works as in the code. Something strange is happening on your network;
please check with e.g. tcpdump.

Regards,
        -is