3.0.4 HOST command support

[habanero]

I'm new to beyond compare and so far, very nice software. I set up an FTP server using WS_FTP Server 5 and BC 3.0.2 and everything worked great until installing the 3.0.4 update. Now BC sends the HOST command and the server responds with "504 unknown host" error and stops. I've looked thru the WS_FTP server docs and cannot find a way to make it work again. Is there a way to disable the HOST command support in BC? Any input would be greatly appreciated.

Regards,

Habanero

[Zoë]

There isn't a way to disable it (yet). Can you post a log showing the failed connection?

[habanero]

Thanks for the quick (instantaneous) reply! Here is the log (I removed personal info):

9/3/2008 3:34:11 PM Username: <content removed>
9/3/2008 3:34:12 PM Stat> Connected.
9/3/2008 3:34:12 PM Recv> 220 <content removed> X2 WS_FTP Server 5.0.5 (3078497007)
9/3/2008 3:34:12 PM Sent> HOST [<content removed>]
9/3/2008 3:34:12 PM Recv> 504 unknown host
9/3/2008 3:34:12 PM Sent> USER <content removed>
9/3/2008 3:34:12 PM Stat> Disconnected.
9/3/2008 3:34:12 PM Connection Closed Gracefully.
9/3/2008 3:34:12 PM Load comparison: <content removed> <->

What about running the FEAT command prior to the HOST command to see if it is supported? Or an option to disable it would work as well.

Thanks,

Habanero

[Zoë]

Well this is annoying...

WS_FTP 5 and 6 both support HOST and give correct responses if you send a valid host. Neither includes it in the FEAT response and neither supports a pre-login FEAT. If you send an incorrect HOST to WS_FTP 5 it disconnects immediately; v6 just returns an error and lets you continue.

It looks like issuing a pre-login FEAT will work around the issue, but effectively disables HOST support for all current WS_FTP versions. I've sent them an email asking their opinion, but that's what I'm leaning towards for now. The other alternative is to just detect the WS_FTP 5 disconnect and automatically reconnect without sending HOST, which is what FTP Voyager does.

[habanero]

Thanks for the investigation. You mentioned if a valid host is sent, it will work. Could I have WS_FTP configured wrong? Note there are NAT routers on both ends. I have the host on WS_FTP configured as the WAN IP, and that's what is sent via the HOST command by BC. Why does WS_FTP reply with unknown host if the IPs match?

Regards,

Habanero

[Zoë]

It doesn't follow the spec regarding IP addresses, so it only accepts host names, and if it's listening on multiple controllers it looks like it needs a dedicated "virtual server" for each. For example, I have a server set up, listening on the private network, and "host servername" works, but "host localhost", "host 1.2.3.4", and "host 127.0.0.1" all fail, even though I can connect without HOST for all of them, and the "address" field is "$virtual".

I don't think the spec is ever going to be implemented the way it's written, because it isn't practical. I've actually changed my mind and I think it's better to match FTP Voyager's behavior completely; at least that way there's only one group of incompatible implementations.

[habanero]

I agree, it makes sense to do what FTP Voyager does. Would it be hard to add a check box option in the FTP profile to enable/disable HOST support? That would allow users to disable it if they don't need the support. Will any changes be in the next update?

Thanks for your responsiveness, which is rare anymore in this world. You have a very nice product here. I will continue to evaluate it to make sure it fits our needs before purchasing.

Habanero

[Zoë]

The next release will work exactly like FTP Voyager does and will have an option in the profiles to disable HOST support.

[habanero]

Excellent! Thanks for all your troubleshooting efforts.

Habanero