Shulou(Shulou.com)06/01 Report--

1) combine the / var/log/secure file to seal off the IP with ssh login failures greater than N

N=3SEC_FILE=/var/log/securefor ip in `grep "Failed password" $SEC_FILE | grep-Eo "([0-9] {1 INPUT 3}\.) {3} [0-9] {1 if 3}" | sort-n | uniq-c | awk'{if ($1 > $N) print $2} '`doiptables-An INPUT-s $ip-p tcp-- dport 22-j DROPdone

2) check the number of connections in each state of the TCP process

Netstat-n | awk'/ ^ tcp/ {+ + S [$NF]} END {for (an in S) print print S [a]}'| | netstat-n | awk'/ ^ tcp/ {print $NF}'| sort | uniq-c example: [root@huangzp ~] # netstat-n | awk'/ ^ tcp/ {print $NF}'| sort | uniq-c 3 ESTABLISHED

3) View and count the number of IP connections

Netstat-ntu | awk'{print $5}'| grep'[0-9]'| cut-d:-F1 | sort | uniq-c example: [root@huangzp ~] # netstat-ntu | awk'{print $5}'| grep'[0-9]'| cut-d:-F1 | sort | uniq-c 1 140.205.140.205 1 183.14.171.25 1 183.14.171.44

4) Statistics of png file size

Find /-name *. Png-exec wc-c {}\; | awk'{print $1}'| awk'{sum=sum+$1} END {print sum} 'example: [root@huangzp ~] # find /-name *. Png-exec wc-c {}\; | awk' {print $1}'| awk'{sum=sum+$1} END {print sum} '22473132

5) Recursive catalog creation

Mkdir-p {0.10} / {0.10}

6) commands that remove # and blank lines from linux text

Cat / usr/local/apache2/conf/httpd.conf | grep-Ev'(^ # | ^ $)'

7) use tcpdump to sniff the access to port 80 to see who is the highest

Tcpdump-I eth0-tnn dst port 80-c 10 | awk-F "."'{print $1 "." $2 "." $3 "." $4}'| sort | uniq-c

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