smtp xinetd help

[atomicmak]

i heared putting ip stack in smtp_psa would help block attack from ip range.

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service smtp
{
socket_type = stream
protocol = tcp
wait = no

no_access = 121.1.128.0/17
no_access = 121.1.64.0/18
no_access = 121.128.0.0/11



===================================

someone said in this forum that adding one param to smtp_psa (banner_fail) would show the ip blocked by smtp in a log so i added like this in smtp_psa.

===================================
banner_fail = /var/log/smtp.fail
disable = no
user = root
instances = UNLIMITED
server = /var/qmail/bin/tcp-env
server_args = /var/qmail/bin/relaylock /var/qmail/bin/qmail-smtpd /var/qmail/bin/smtp_auth /var/qmail/bin/true /var/qmail/bin/cmd5checkpw /var/qmail/bin/true
per_source = 20
===================================

but still i am not getting smtp.fail log or nothing being written in that file.

can anyone help me on this ?

the thread i ead is

http://forum.swsoft.com/showthread....ge=15&highlight=formmail exploit&pagenumber=1