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List all IP addresses connected to your Server
Below is an Unix command to list all the IP addresses connected to your server on port 80. Output – Total connections by IP, from highest to lowest. Note This command is useful to detect if your server is under attack, and null route those IPs. Read this null route attacker IP story. Let break above lengthy command into pieces : 1. netstat -tn 2>/dev/null Uses netstat to list all network connections, ins and outs. -n – Display numeric only, don’t resolve into name. -t – Display only TCP connections. Output 2>/dev/null Redirect all unwanted output to /dev/null, a special place to absorb all output and clear it. 2. grep…
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How To Find Word(s) On Files in Linux
Do the following: -r or -R is recursive, -n is line number, and -w stands for match the whole word. -l (lower-case L) can be added to just give the file name of matching files. Along with these, --exclude, --include, --exclude-dir flags could be used for efficient searching: This will only search through those files which have .c or .h extensions: grep --include=\*.{c,h} -rnw '/path/to/somewhere/' -e "pattern" This will exclude searching all the files ending with .o extension: grep --exclude=*.o -rnw '/path/to/somewhere/' -e "pattern" For directories it’s possible to exclude a particular directory(ies) through --exclude-dir parameter. For example, this will exclude the dirs dir1/, dir2/ and all of them matching…