Clear all lines in a csf deny file that contains text: Added by Fail2Ban

bmxakias · 08-23-2017, 08:18 AM

Hello

I am looking for an easy way to clear all lines like:

Code:

123.456.789.000 # Added by Fail2Ban for nginx-get-f5 - Wed Aug 23 13:02:55 2017

from:

Code:

/etc/csf/csf.deny

by checking the text: Added by Fail2Ban

How can i do that with a simple command from ssh on my Centos server?

Thank you

rtmistler · 08-23-2017, 08:29 AM

Suggest you look up the 'd' option for the sed command.

TenTenths · 08-23-2017, 08:32 AM

Code:

 grep -v Fail2Ban /etc/csf/csf.deny > /tmp/csf.deny;mv /tmp/csf.deny /etc/csf/csf.deny

You're welcome....

bmxakias · 08-23-2017, 08:44 AM

I think that can be done direct to the file without creating another file in /tmp folder and so on...... ?

rtmistler · 08-23-2017, 08:47 AM

Quote:

Originally Posted by bmxakias

I think that can be done direct to the file without creating another file in /tmp folder and so on...... ?

I agree, and ...

Quote:

Originally Posted by rtmistler

Suggest you look up the 'd' option for the sed command.

TenTenths · 08-23-2017, 08:48 AM

Quote:

Originally Posted by bmxakias

I think that can be done direct to the file without creating another file in /tmp folder and so on...... ?

Sure, go read rtmistler's reply and read up on sed

Edit: I never said my method was the best, simply an alternative.

bmxakias · 08-23-2017, 12:55 PM

@TenTenths

No offense and thanks for your reply

@rtmistler

Thanks i will try to find a way to do it.....

TenTenths · 08-23-2017, 01:01 PM

Quote:

Originally Posted by bmxakias

@TenTenths

No offense and thanks for your reply

None taken.

bmxakias · 08-23-2017, 01:22 PM

Can't find a sample with sed -d option on how to do that

Any help please?

Any sample?

Sefyir · 08-23-2017, 01:28 PM

A quick search like "delete matching lines with sed" will do wonders
https://duckduckgo.com/?q=delete+matching+lines+sed

http://stackoverflow.com/questions/5410757/ddg#5410784

Quote:

sed '/pattern to match/d' ./infile

bmxakias · 08-23-2017, 02:21 PM

Quote:

sed '/Added by Fail2Ban/d' /etc/csf/csf.deny

Like this?

rtmistler · 08-23-2017, 02:26 PM

Quote:

Originally Posted by bmxakias

Like this?

Yes and try it. Because the output result will go to stdout and in fact to get it to that file, you'd need to use the -i flag for sed or pipe the result to a file. The -i flag will perform the changes "in place", however it is a great idea to see the outcome piped to stdout first to validate your syntax. I believe you may need a leading 's', as in:

Code:

's/<string>/d'

bmxakias · 08-23-2017, 02:29 PM

Maybe like this then?

Quote:

sed -i 's/Added by Fail2Ban/d' /etc/csf/csf.deny

MadeInGermany · 08-25-2017, 01:22 AM

Like the s command in sed (substitute)
there is the d command (delete).

MadeInGermany · 08-25-2017, 06:24 AM

Quote:

Originally Posted by bmxakias

Like this?

Yes like this.
Add -i option to direct the output back to the file.

Code:

sed -i '/Added by Fail2Ban/d' /etc/csf/csf.deny