(address . bug-guix@gnu.org)
building /gnu/store/6smkn7dk6m8w7h7yw0v0lfn0w72q4zxm-agg-2.5.tar.gz.drv...
Starting download of /gnu/store/8pgqgdcmc10ncj8bhkyi5ilx6mmfk8y1-agg-2.5.tar.gz
From ftp://ftp.fau.de/gentoo/distfiles/agg-2.5.tar.gz...
Throw to key `ftp-error' with args `(#<input-output: socket 13> "PASV" 501 "PASV: Operation not permitted\r")'.
In comparison, that works just fine with wget:
$ wget -d -c 'ftp://ftp.fau.de/gentoo/distfiles/agg-2.5.tar.gz'
[...]
==> SIZE agg-2.5.tar.gz ...
--> SIZE agg-2.5.tar.gz
213 564313
564313
conaddr is: 2001:638:a000:1021:21::1
==> EPSV ...
--> EPSV 2
229 Entering Extended Passive Mode (|||51160|)
respline is 229 Entering Extended Passive Mode (|||51160|)
trying to connect to 2001:638:a000:1021:21::1 port 51160
Created socket 4.
fertig. ==> RETR agg-2.5.tar.gz ...
--> RETR agg-2.5.tar.gz
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