Trying to get my head round firewall stuff but I'm obviously doing something really dumb which is stopping me from getting ahead with implementing my iptables script. I can enter (sudo) iptables commands at the command line no problem but as soon as I try running the same command(s) within a bash script I get 'no chain/target match by that name' error message. Even a simple line e.g. 'iptables -L' when scripted will produce this error. Is this an ownership/permissions issue with bash rather than an iptables issue? Thanks for any assistance anyone can offer.

I guess it's a permission issue. The simply test I recommend is to run iptables -L in a script as root, what should obviously work nicely. Then, add sudo when needed (or change the user your script runs as).

Thank you for your help

I think the problem was that I copied the original script from a win32 (NTFS) system and it didn't seem to like that. When I re-created the script on the Linux box it executed ok. I knew it would be something dumb I was doing wrong.