Autoforwarding Black Hole

[EricWilliams]

Are there any email protocol experts out there on CD? I've set up two accounts to autoforward new email two each other by accident. I noticed almost right away and remedied the problem, but I've found some interesting behaviors. I have not received an "undeliverable" message regarding the test emails I have sent to my various accounts that would have gotten sucked into this black hole, nor have the emails shown up in either accounts inbox. These are both Gmail accounts that are forwarding to each other. Does anyone know what happens in this situation?

[Jimmy Cao]

I'm willing to guess that Gmail foresaw this potential problem (or exploit) and patched it server-side already, so if it detects this gmail - gmail forwarding loop, it will just break it.

Now, what happens if you have gmail forwarding to non-gmail which forwards back? I'd guess that gmail/the other mail server would catch on pretty fast and stop the emails.

[artdutra04]

Originally Posted by EricWilliams

Are there any email protocol experts out there on CD? I've set up two accounts to autoforward new email two each other by accident. I noticed almost right away and remedied the problem, but I've found some interesting behaviors. I have not received an "undeliverable" message regarding the test emails I have sent to my various accounts that would have gotten sucked into this black hole, nor have the emails shown up in either accounts inbox. These are both Gmail accounts that are forwarding to each other. Does anyone know what happens in this situation?

This black hole would cause a single email to get sent back and forth quite rapidly between the two accounts. I'm guessing this happened so quickly, that Gmail flagged the account as a bulk spamming account and moved the messages into the Spam folder.