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11-28-2006, 01:32 AM
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#1
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Member
Registered: Oct 2006
Posts: 36
Rep: 
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How to stop FTP and Telnet services?
hello,
I have stopped telnet and wu-ftp serivices by following command:
% chkconfig telnet off
% chkconfig wu-ftpd off
when i ftp and telnet they are not availble after it.
but when i check the following file /etc/services i find that ftp is on on both TCP/UDP and similrly telnet is available on TCP/UDP both protocols.
Now do i have to comment out the refrenced lines in file /etc/services or are the services closed by above mentioned command.
kindly guide me
makkays
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11-28-2006, 02:15 AM
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#2
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Senior Member
Registered: Jul 2003
Location: Silicon Valley, USA
Distribution: OpenBSD 4.6, OS X 10.6.2, CentOS 4 & 5
Posts: 3,660
Rep:
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/etc/services is only a name-to-number/number-to-name mapping table. That file does not disable or enable any services.
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11-28-2006, 10:25 PM
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#3
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Member
Registered: Oct 2006
Posts: 36
Original Poster
Rep:
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thanks,
kindly confirm whether After running "chkconfig telnet off " it means that telnet services are off on both TCP/udp ports? and
also is this true that name-to-number/number-to-name mapping is created on installation of OS, so even if i am not using a perticular service the mapping will be there by default.
regards
makkays
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11-29-2006, 02:05 AM
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#4
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Senior Member
Registered: Jan 2005
Location: Roodepoort, South Africa
Distribution: Ubuntu 12.04, Antix19.3
Posts: 3,797
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Quote:
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Originally Posted by makkays
kindly confirm whether After running "chkconfig telnet off " it means that telnet services are off on both TCP/udp ports?
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There is only one telnet service/daemon. Switching it 'off' only means that it does not run (regardless of the protocol).
Quote:
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Originally Posted by makkays
also is this true that name-to-number/number-to-name mapping is created on installation of OS, so even if i am not using a perticular service the mapping will be there by default.
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Yes, although I'm quite sure that it's just a file that is copied from the installation CD during installation (so not really created). |
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11-29-2006, 02:28 AM
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#5
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Senior Member
Registered: Jul 2003
Location: Silicon Valley, USA
Distribution: OpenBSD 4.6, OS X 10.6.2, CentOS 4 & 5
Posts: 3,660
Rep:
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Telnet and FTP only use TCP. The fact that they have reserved UDP ports is from the legacy days of the early Internet.
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11-29-2006, 02:48 PM
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#6
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LQ Newbie
Registered: Nov 2006
Posts: 2
Rep: 
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I want to mention that telnet is controlled by xinetd service in latest version's of Redhat Linux
"Chkconfig telnet off" stop's the telnet session & can also be confirmed from /etc/xinetd.d/telnet with "disable = yes" option
you can alternatively make use of Tcp_wrappers(/etc/hosts.allow) to control telnet
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11-29-2006, 11:42 PM
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#7
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Member
Registered: Oct 2006
Posts: 36
Original Poster
Rep:
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Thanks everybody.the concept is really clear now
regards
makkays
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