This is the command mxallowd that can be run in the OnWorks free hosting provider using one of our multiple free online workstations such as Ubuntu Online, Fedora Online, Windows online emulator or MAC OS online emulator
PROGRAM:
NAME
mxallowd - dynamically whitelist your Mail eXchanger
SYNOPSIS
mxallowd [-d] [-c configfile] [-t whitelist-time] [-p pflog-interface] [-l pcap-filter]
[-F] [-s] [-q] [-p] -f fake-mailserver -r real-mailserver -n queue-num
DESCRIPTION
mxallowd is a daemon which uses libnetfilter_queue (on Linux) or pf and pflog (on BSD) to
allow (or deny) connections to a mailserver (or similar application) if the remote host
hasn't connected to a fake daemon before.
This is an improved version of the so-called nolisting (see http://www.nolisting.org/).
The assumption is that spammers are not using RFC 2821-compatible SMTP-clients and are
sending fire-and-forget spam (directly to the first or second MX-entry without retrying on
error). This direct access is blocked with mxallowd, you'll only get a connection if you
retry.
NOTE: It is highly recommended to install nscd (nameserver caching daemon) or a similar
software in order to speed-up DNS lookups. Since version 1.3, DNS lookups are done in a
thread (so they don't block the main process), however, on very-high-traffic-sites,
mxallowd may show significantly better overall performance in combination with nscd.
OPTIONS
-b, --no-rdns-whitelist
Disable whitelisting all IP-addresses that have the same RDNS as the connecting one
(necessary for google mail)
-c, --config
Specifies an alternative configuration file (instead of /etc/mxallowd.conf)
-t, --whitelist-time
Specify the amount of time (in seconds) until an IP-address will be removed from
the whitelist
-s, --stdout
Log to stdout, not to syslog
-q, --quiet
Don't log anything but errors.
-f, --fake-mailserver
Specify which IP-address the fake mailserver has (connecting to it will whitelist
you for the real mailserver)
-r, --real-mailserver
Specify which IP-address the real mailserver has
-F, --foreground
Do not fork into background, stay on console
-n, --queue-num (only available when compiled for netfilter_queue)
Specify the queue number which will be used for the netfilter_queue-link. This has
to be the same which is specified in the iptables-rule and it has to be specified,
there is no default.
-p, --pflog-interface (only available when compiled for pf)
Specify the pflog(4) interface which you configured in pf(4). The default is
pflog0. Also see the pcap-filter-option if you use an interface which does not only
get smtp-traffic.
-l, --pcap-filter (only available when compiled for pf)
Specify the filter for pcap. The default is "port 25". See tcpdump(8) for more
information on the filters.
Use mxallowd online using onworks.net services