How to check all open ports on linux machine and block
unsed ports????????
Answers were Sorted based on User's Feedback
Answer / sureshreddy
#netstat -tulp
or
#netstat -tulpn
to verfy the open ports
| Is This Answer Correct ? | 17 Yes | 1 No |
Answer / parthasarathy k
#nmap -v localhost for tcp
#nmap -sU localhost for udp
| Is This Answer Correct ? | 12 Yes | 6 No |
Answer / manoj
netstat -t(tcp)
netstat -u(udp)or
netstat -tulpn
to verfy the open ports
to block u have to use iptable & tcp_wrappers( hosts.deny
file)
| Is This Answer Correct ? | 6 Yes | 1 No |
Answer / pankaj pal
To check all the Open Ports use command
netstat - tulpn
To Block Ports for eg.22 and 80 as requested by Ashish
iptables -t filter -A INPUT -s!192.168.0.0/24(IP which you
want to allow) -p tcp -d (destination server IP) --dport
22 -j DROP
iptables -t filter -A INPUT -s!192.168.0.0/24(IP which you
want to allow) -p tcp -d (destination server IP) --dport
80 -j DROP
| Is This Answer Correct ? | 5 Yes | 0 No |
Answer / ashish
Hi!! All
Can you give an example to block certain ports
like block 22 & 80.
Any help will be appreciated.
Ashish
| Is This Answer Correct ? | 2 Yes | 1 No |
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