I have written this procedure to help you on importing DNS zone in an existing Bind server. In the following procedure, I suppose the file to import have the “.dns” extension. To import these DNS zone files, you have to follow these steps :

• change the content of the zone files (SOA and NS records)
• update the named.conf file on both master and slave dns servers
• load the zones

All the following sed command can be run without the option “-i” for testing without writing the file.

To update both SOA and NS records, you can use the sed command :

• create a temporary folder : mkdir /tmp/zone_files
• copy the zone files to the folder created above
• change the SOA : sed -i ‘s/ns1.domain.old. hostmaster.domain.old./ns1.domain.new. hostmaster.domain.new./g’ *.dns
• delete the old NS entries : sed -i ‘/NS/d’ *.dns
• add the first new NS record : sed -i ‘s/\t\t\t\t)/\t\t\t\t)\n\t\t\tNS ns2.domain.new./’ *.dns
• add another NS record if applied : sed -i ‘s/\t\t\t\t)/\t\t\t\t)\n\t\t\tNS ns3.domain.new.’ *.dns
• backup your named.conf file : cp /etc/bind/named.conf /etc/bind/named.conf.bkp
• create the import_zone.py with this content :

  #!/usr/bin/python
  
  import os, sys
  import re
  
  path = "/tmp/zone_files/"
  dirs = os.listdir( path )
  
  with open("/etc/bind/named.conf", "a") as myfile:
          for file in dirs:
                  zone = re.sub('\.dns$', '', file)
                  zone2add = 'zone "' + zone + "\" {\n\ttype master;\n\tfile \"/var/lib/bind/" + file + "\";\n};\n\n"
                  myfile.write(zone2add)

• run the script and check the content of the named.conf : python import_zone.py
• reload the dns zones : rndc reload
• You can now change the named.conf on the secondary dns servers with the following script (change the ip address with your own master dns server ip address) :

  #!/usr/bin/python
  
  import os, sys
  import re
  
  path = "/tmp/zone_files/"
  dirs = os.listdir( path )
  
  with open("/etc/bind/named.conf", "a") as myfile:
          for file in dirs:
                  zone = re.sub('\.dns$', '', file)
                  zone2add = 'zone "' + zone + "\" {\n\ttype slave;\n\tmasters { 10.1.2.3; };\n\tfile \"/var/lib/bind/" + file + "\";\n};\n\n"
                  myfile.write(zone2add)
  

• reload the dns zones : rndc reload

Do not hesitate to leave a comment if you have any problem or questions with this procedure.