Dynamic and Secure DNS Tianyi Xing

 Establish a dynamic and secure DNS service in the mobicloud system

 By mid-term  Establish a DNSSEC server within the mobicloud system ▪ Successfully installed ▪ at configuration stage  Configure the network to make sure DNSSEC server serve the right purpose in the mobicloud system  By Final  Perfect its function ▪ Dynamically cooperate with the user ID and IP address ▪ Dynamically update the ip(ID) and domain pair  Documentation 3

 Hardware  Dell Rack Server  Switches  Software  Ubuntu  Xenserver 5.6  Xencenter  Dnssec-keygen  Bind9  dhcpd 4

 1. Semi-automatically DNS  Everytime VM is created, backend part of the mobicloud system reads UserID from the DB and register “UserID.mobicloud.asu.edu” in DNS server.  2. Dynamic secure DNS+DHCP  Everytime VM is created, DHCP will automatically register “hostname.mobicloud.asu.edu” at the DNS.

 Create VM  VM Get ip addresses from DHCP  DHCP assign the DNS to VM as the Default DNS  We retrieve the ip addresses from the VM (vm.getrecord())and save it into a string  We get userName and userID from web session and pass that into the DNSupdate method

 Generate the domain name based on the userName. (i.e., terry.mobicloud.asu.edu)  SSH on to the DNS server and write all the command into a script file.  Run that script with nsupdate command  Use ping to check, ping terry.mobicloud.asu.edu, then it works !!!

 Pros ▪ Mobicloud system has more flexibility on the domain name. Not just like the hostname.domain.com ▪ Backend part has more control on update DNS ▪ Mobicloud system can directly run command on the DNS server anytime it wants  Cons ▪ Inconvenient ▪ More workload at the backend part ▪ Once the ip is changed, the mobicloud system has trouble on updating the new domain and ip pair

 Define a class in DHCP server to identify the template VM  Assign a temporary IP address  User Hostname as the identifier  It is also allowed to use mac address to identify VM  Once ip is updated from DHCP, DHCP will register the VM in DNS again

 Create VM  Get ip from DHCP server  Backend sent the UserName and Label to SSH server  Let the SSH server change the hostname(UserID and Label) of the VM  Send the DHCP request again with new hostname  Update DNS with key

 Pros  Backend do not need to read from the Database and get the userID and define the schema of the domainname, once the VM is created, “hostname.mobicloud.asu.edu” is registered.  Whenever VM get new ip, the DHCP will dynamically update the zone entry in the DNS  Cons  Only when ip is updated, the DNS is updated

 Clone a new VM  New VM gets a short term ip from DHCP server  Check the domain name ”hostname.mobicloud.asu.edu”  Change the hostname to newhostname  DHCP request  Check with the domain newhostname.mobicloud.asu.edu