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DCC (from

DCC (Distributed Checksum Clearinghouse) is a system similar to Razor. It supports fuzzy checksums and therefore detects some more spams than Razor does at the moment.

To install it, perform the following steps:

	tar xfvz dcc.tar.Z
	cd dcc-2.3.167
	CFLAGS="-O2 -fstack-protector" DCC_CFLAGS="-O2 -fstack-protector" ./configure && make && make install

You might want to replace the configure call with something like this to get an FHS compliant install:

	./configure \
		--bindir=$(PREFIX)/bin \
		--libexecdir=$(PREFIX)/lib/dcc \
		--mandir=$(PREFIX)/man \

It's recommended to run the persistent dccifd daemon for sites scanning more messages.

This method assumes you are not using DCC / dccifd for anything else than scanning with SA. If you are using any other features like DCC server, greylisting etc, see:

	# create dcc user to run dccifd safely (Linux specific useradd arguments)
	useradd -m -U -d /var/dcc -s /bin/sh dcc 
	# homedir needs to be owned by the user
	chown -hR dcc:dcc /var/dcc
	# start dccifd as dcc user (you could add this to /etc/rc.local for system startup, or see your OS manual)
	su - -c '/var/dcc/libexec/dccifd' dcc

Finally call cdcc:

        cdcc info

The last command will give some output. The output should contain lines like this:,-         RTT+0 ms    anon,-         RTT+0 ms    anon

There should be *at least one*, preferably more than half a dozen, of the public DCC servers listed. If this is not the case, a likely cause is an interfering firewall (see UsingDcc).

More info is at UsingDcc.

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