[noam]

Hey all,

I'm using Retrospect 5 for OS X for nightly FTP backups to an off site server. Suddenly, Retrospect is unable to contact the server. I've seen this in the past and it's been due to the Mac OS 10 fire wall; but my OS 10 firewall is turned off. I recently installed a built-in DSL router with network address translation, although I think it was working for a little while after the router was installed. It definitely seems to be related to the firewall and network address translation, but I can't tell where. I've tried it using both passive and active FTP in the network preferences pane. Any suggestions?

Noam

[podragon]

I'm no expert, but if it just suddenly stopped working (that is soo annoying isn't it?) and your hardware setup remains unchanged, I would suspect some sort of configuration problem. A few things I would try:

1) If you have a separate DSL modem (typically provided by your DSL-provider) I would try to connect directly to this modem (without the new DSL-router) and setting your computer up to use the fixed or dynamic (DHCP) IP as instructed by your DSL-provider. If this works, you've isolated the problem to your DSL-router setup. If not there must be something else causing the trouble.

2) Make sure the server is actually available. Will the server accept FTP connections using a separate FTP-client program (or the terminal), presuming you know the account/password?

3) If your NATing router works as a firewall and supports port-forwarding (like the Airport Basestation does) you may have to set your router to forward ftp-traffic to the correct port on your computers NATed, local-network IP address. (Port 21 for ftp, port 22 for ssh). I think this may be uneccessary if you are only using passive mode for ftp, like you say you have tried, but I am not sure of this (as I said I'm not an expert), so maybe it's worth looking into.

Hope this helps.
Good luck!

[zerologic]

Knowledge base

TITLE: Does the Internet Backup Sets (FTP Backup) work in passive mode or active mode?

Article ID: 25576

Date Created: 2001-01-10
_
Date Modified: 2003-05-20

Discussion: Retrospect will only write to an FTP site in Active mode - we can't transmit
in Passive mode.

[noam]

Thanks for that link to the Dantz site, which contains a link to an FTP primer. Since Active FTP doesn't play well with firewalls, I fixed this by pointing my router's DMZ to my computer's IP address.

However, that leaves my machine way open. I'd like to turn on the Mac OS X built-in Firewall, but that again seems to break Retrospect! I've even turned on FTP services in the Sharing prefs panel (which should open the correct ranges of ports in the firewall), but to no avail. Are there some other ports that need to be opened up?

Thanks,
Noam