If SG egress rules are present, check if they interfere with active transfers

[Castaglia]

If any of the security groups (SGs) for the instance have egress rules, then mod_aws should check them on startup, just as it does for ingress rules, to see the egress rules would prevent/interfere with active data transfers. The check should encompass both restricted ports and restricted addresses; if the instance cannot connect back to the allowed ingress addresses, that would prevent active transfers from working as expected.

[Castaglia]

If the egress rules are configured such that they match the ingress addresses, and no where else, this can help prevent the "FTP bounce" attack. Something to mention in the module docs, at least.