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Service (Amazon S3)
19 - ami plugin for Amazon Simple Storage Service (Amazon S3)
20 - sftp plugin for SSH File Transfer Protocol
21 - ebs plugin for Elastic Block Storage
22 - local plugin
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seconds, for example:
# nc -p 16000 -w 30 examplehost.tld 22
If firewalling is in place and you need to originate your connection from a specific IP address to open a port, then you can enter:
# nc -s 1.2.3
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.nmap.org (64.13.134.52):
Not shown: 994 filtered ports
PORT STATE SERVICE VERSION
22/tcp open ssh OpenSSH 4.3 (protocol 2.0)
25/tcp closed smtp
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and then explicitly allow certain users access. It's similar to the deny by default approach I touched on in another article [3]. To achieve this, the /etc/hosts.deny file would look like this:
sshd: ALL
To allow
