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How to hide Nameserver software version on Centos 7

Hide DNS Software Version

Sometimes a new vulnerability is found in DNS software and script kiddies are scanning the Internet to exploit unpatched systems. It's a best practice to hide software version on your DNS servers, although this is not a real protection it just makes a little harder to find your servers via scanning.
Use dig command to find which version is running on your name servers:
$ dig +short @ns1.example.com version.bind txt chaos
"9.8.2rc1-RedHat-9.8.2-0.23.rc1.el6_5.1"

Bind

To hide version in when using Bind, open named.conf configuration file using your favorite editor, go to options section and set a custom version string using version option.
Example:
// /etc/named.conf
options {
  // Hide bind version
  version "unknown";
};
Restart the server (use bind9 instead of named on systems based on Debian):
$ sudo service named restart
Stopping named: .                                          [  OK  ]
Starting named:                                            [  OK  ]
Verify that server is returning new version string:
$ dig +short @ns1.example.com version.bind txt chaos
"unknown"




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So what can i do for that problem ?

Yes, you have to fix the error .

Environment Details:
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CWP: How to Configure Let's Encrypt SSL Certificate for your server Hostname/FQDN on CWP7.admin

I wrote a blog on http://forum.centos-webpanel.com regarding Let's Encrypt SSL Certificate for CentOS Web Panel when "Letsencrypt Manager"  option was exist under Apache Settings >> Letsencrypt Manager >> Install Letsencrypt .

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N.B: I am using the below cipherlist 
https://cipherli.st/
https://mozilla.github.io/server-side-tls/ssl-config-generator/
https://wiki.mozilla.org/Security/Server_Side_TLS

So now I am writing this solution again for all of guys and I hope that it will be 100% working again on your CentOS-Webpanel as mine .

Environment Details:
CPU Model: Intel(R) Xeon(R) CPU X3440 @ 2.53GHz
CPU Details: 2 Core (2527 MHz)
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