Não tenho certeza de como isso é atualizado, mas você pode usar dois comandos:
$ wget --spider -r --no-parent http://archive.canonical.com/ubuntu/pool/partner/
(...SNIP...)
Found no broken links.
FINISHED --2018-05-20 20:01:58--
Total wall clock time: 1m 35s
Downloaded: 507 files, 1.2M in 0.4s (3.24 MB/s)
$ ls -l archive.canonical.com/ubuntu/pool/partner/
total 68
drwxrwxr-x 4 rick rick 4096 May 20 20:00 a
drwxrwxr-x 4 rick rick 4096 May 20 20:00 c
drwxrwxr-x 6 rick rick 4096 May 20 20:00 d
drwxrwxr-x 4 rick rick 4096 May 20 20:00 e
drwxrwxr-x 9 rick rick 4096 May 20 20:01 g
drwxrwxr-x 3 rick rick 4096 May 20 20:01 h
drwxrwxr-x 3 rick rick 4096 May 20 20:01 i
drwxrwxr-x 3 rick rick 4096 May 20 20:01 k
drwxrwxr-x 4 rick rick 4096 May 20 20:01 m
drwxrwxr-x 3 rick rick 4096 May 20 20:01 n
drwxrwxr-x 5 rick rick 4096 May 20 20:01 o
drwxrwxr-x 3 rick rick 4096 May 20 20:01 p
drwxrwxr-x 3 rick rick 4096 May 20 20:01 s
drwxrwxr-x 14 rick rick 4096 May 20 20:01 t
drwxrwxr-x 3 rick rick 4096 May 20 20:01 u
drwxrwxr-x 3 rick rick 4096 May 20 20:01 v
drwxrwxr-x 4 rick rick 4096 May 20 20:01 x
Agora você tem um índice completo (espero) de todos os pacotes disponíveis em sua unidade. Para verificar o que está disponível na categoria a
:
$ ls archive.canonical.com/ubuntu/pool/partner/a
acroread adobe-flashplugin
O tamanho da lista é nominal, portanto, convém mantê-lo em sua unidade ou excluí-lo:
$ du -h -d1 archive.canonical.com/ubuntu/pool/partner/
32K archive.canonical.com/ubuntu/pool/partner/g
12K archive.canonical.com/ubuntu/pool/partner/e
8.0K archive.canonical.com/ubuntu/pool/partner/n
12K archive.canonical.com/ubuntu/pool/partner/x
8.0K archive.canonical.com/ubuntu/pool/partner/v
12K archive.canonical.com/ubuntu/pool/partner/c
8.0K archive.canonical.com/ubuntu/pool/partner/p
8.0K archive.canonical.com/ubuntu/pool/partner/i
8.0K archive.canonical.com/ubuntu/pool/partner/s
12K archive.canonical.com/ubuntu/pool/partner/a
52K archive.canonical.com/ubuntu/pool/partner/t
8.0K archive.canonical.com/ubuntu/pool/partner/k
8.0K archive.canonical.com/ubuntu/pool/partner/u
8.0K archive.canonical.com/ubuntu/pool/partner/h
16K archive.canonical.com/ubuntu/pool/partner/o
20K archive.canonical.com/ubuntu/pool/partner/d
12K archive.canonical.com/ubuntu/pool/partner/m
248K archive.canonical.com/ubuntu/pool/partner/