Re: [9fans] ftpfs shows empty /n/ftp after login

[Bakul Shah <bakul@bitblocks.com>]

On Thu, 25 Jun 2015 19:25:36 +0200 "Nils M Holm" <nmh@t3x.org> wrote:
>
> Came back to Plan 9 recently, and I'm running into some trouble.
> I'm running Plan 9 on QEMU and wanted to use ftpfs to exchange
> data with my FreeBSD system.
>
> When logging in via ftpfs, though, I get an empty /n/ftp directory.

My guess: you are using qemu's networking and can only make
outgoing connections but not accept incoming connections and

The default ftp protocol is to have the server connect back to
you. To go past firewalls and NAT gateways these days you use
ftp passive mode (i.e. force the client to make a connection to
a separate server port). My guess is ftpfs requires active
mode connection (but should be easy to change).

Otherwise use qemu in bridged networking mode so that a guest
os can accept any connection. I can't recall the details at
the moment but you have to use FreeBSD bridge device and add
tap ports to it.

In any case, here are some debugging ideas: Try tcpdump on
freebsd or the qemu host? Are you ftping to the qemu host
machine or another?  Does 9fs sources works? There is also
ratrace (sort of like strace) - pick up my modifications from
sources/contrib/bakul/cmd as it separates trace output from
normal output.

ratrace -o tracefile ftpfs ...