Shell script fourth-common small script

Shell Script Fourth-common small script

1, the system process according to the size of memory consumption display out

# PS-E-o "%c:%p:%z:%a"|sort-k5-nr

2. The system process is displayed by CPU size

# PS-E-o "%c:%p:%z:%a"|sort-nr or # PS aux--sort-rss

3, find the current directory occupies 0 bytes of files and delete

# Find/-type f-size 0-exec rm-rf {}\; # This command does not work with 0 -byte files on the root directory

4. Match a line in a file and replace it with content

#sed-I '/root/s/no/yes'/etc/ssh/sshd_config # matches first to Root, Then replace the line no with Yes

5.TCP Packet capture tool analysis Port data stream

# tcpdump-c 10000-i eth0-n DST Port 80

6. Delete all empty directories

# Find/data-type d-empty-exec rm-rf {}; # It is best not to execute this command in/directory

7. Forward the requestfrom the port to the 8080 Port

#iptables-A prerouting-p tcp-m TCP –dport80-j DNAT –to-destination 127.0.0.1:8080

8. The Apache access log access.log count the number of IPs and their accesses, listed by traffic name

    # Cat Access.log | awk ' {print $} ' |sort| uniq-c |sort-rn |head-10

9. Lock key files to prevent malicious tampering | | Unlock to chattr-i

# chattr +I/ETC/PASSWD chattr +i/etc/inittab

Change the file descriptor size to the maximum 65535 The next login takes effect, View File descriptor value size

# echo ' *-nofile 65535 ' >>/etc/security/limits.conf ; Ulimit-n

11. Synchronize the hosts in 1.105/etc via SSH Channel File into the native /data directory

# rsync-avz-e ' ssh-p ' [email protected]:/etc/hosts/data/

kill Port-related processes

# Lsof-i: 80|grep-v "PID" |awk ' {print ' kill-9 ', $ $} ' |sh

takeout the number of times the Shell appears in the /etc/passwd file , Shell refers to the back/bin/bash,/sbin/nologin

# cat/etc/passwd|awk-f: ' {print $7} ' |sort|uniq-c

14. found in directory /TMP 100 a start the file and then save the first line of these files to the file file in

# Find/tmp-type F-name "A *" | Head-n 100 | Xargs head-q-N 1 >> file

15, anti-attack script, Enterprise utility small script http://blog.csdn.net/linuxlsq/article/details/52606408

Shell script fourth-common small script