10.2. DNS

10.2.1. About this menu

In this menu, we provide DNS service for external use. Customers can easily use the DNS server in order to provide expert knowledge for DNS servers, necessary construction, operation and security measures on behalf of customers on this menu.
This makes it easy to set up your own domain for resources such as bare metal server and virtual server of this service and make it public to the outside.
By combining with a load balancer etc., it becomes possible to build a large-scale system with high availability.

10.2.1.1. Menu Features

Features of this menu are as follows.

1. Easily create, edit and delete record sets in zones and zones as DNS services

You can easily create, edit, and delete zones and record sets from the portal (GUI).
By doing this, it is easy to set up customer’s domain as a resource of this service and publish it to the Internet.

2. It is possible to build a highly available Web system

The name server of this menu is distributed in multiple locations around the world, and host information can be distributed and managed.
In addition, it is possible to combine DNS round robin and load balancer to build a highly available, large scale Web system etc.

3. Provide OpenStack compatible to API

API is provided in this menu. By using the API, it is possible to execute record definitions and rewriting scripts.
In addition, API of this menu is compatible API of OpenStack’s DNS project (Designate).
Therefore, customers already using the OpenStack API can use this menu smoothly.

Overview of DNS service image

概要

10.2.2. Description of Respective Menus

10.2.2.1. DNS Menu

  • In this menu, we will provide an external content server (authoritative DNS server).

  • You can create, edit, delete zones, create, edit, and delete record sets contained within them.

  • Both forward and reverse settings are possible for record sets.

  • Supports wildcard entries.

The record set that can be set up and the corresponding forward and reverse type are as follows.

Recordset

 

Descriptions

Forward

A record

Bind the host name to the IPv4 address.

 

AAAA record

Bind the host name to the IPv6 address.

 

CNAME record

Set a different host name for the host name.

 

MX record

Set up the mail server. The lower the priority value, the higher the priority.

 

NS record

Specify the DNS server name of the domain.

 

TXT Record

Set the text information related to host and domain.

 

SRV Record

Specify the location of the service for the domain name.

 

SPF Record

It manages the list of IP addresses of authorized servers that can send mail.

 

SOA Record

Set zone (domain) information.

Reverse

PTR Record

Bind the IP address to the host name.

In this menu, 4 redundant name servers are set as a name server group, and when you create a zone, the created zone is assigned to one name server group. Recordsets created in the zone are automatically registered in the four name servers in the name server group assigned to the zone.

The name server information of this menu is as follows.

Name server group

Host Name

Region

Name server group 1

dns101-1.jp1.ecl.ntt.com. JP1
  dns101-2.uk1.ecl.ntt.com. UK1
  dns101-3.us1.ecl.ntt.com. US1
  dns101-4.sg1.ecl.ntt.com. SG1

Name Server Group 2

dns102-1.jp1.ecl.ntt.com. JP1
  dns102-2.uk1.ecl.ntt.com. UK1
  dns102-3.us1.ecl.ntt.com. US1
  dns102-4.sg1.ecl.ntt.com. SG1

Name Server Group 3

dns103-1.jp1.ecl.ntt.com. JP1
  dns103-2.uk1.ecl.ntt.com. UK1
  dns103-3.us1.ecl.ntt.com. US1
  dns103-4.sg1.ecl.ntt.com. SG1

Note

  • Full service resolver (cache server) function is not provided. Customers are advised to prepare DNS resolvers.

  • Domain acquisition is not done, so we ask that you prepare the domain separately.

  • This menu provides external DNS service. DNS for internal use is not provided.

  • Zone transfer is not supported.


10.2.3. Available Functions

In this menu, you first create a zone (a unit for managing domains in this menu, 1 domain is 1 zone).
After creating the zone, by creating a record set (name and IP address, or information mapping a set of name and name) in the zone,
The setting is reflected in the name server, and DNS can be used.

10.2.3.1. Zone

Setting items when the zone is created

Please set the following items when creating a zone. After setting various items, pressing the “Create” button creates the zone.

Setting item List when the zone is created

Items

Settings

Details

Action

Create Zone

Domain
Enter the domain name to be set as the zone. Up to 128 characters can be entered.
NOTE: If you create the same zone as the already set zone (including other tenants and other contracts)
A name server group containing zones that have already been set up
(in other words, the name server group to which the zone belongs)
A different name server group is assigned to that zone.
NOTE: The maximum number of registrations in the same zone is 3.

Customer Portal / API

  Description
It is possible to enter arbitrary comments in the zone to be set.
Up to 255 characters can be input (Japanese is also possible)

Customer Portal / API

Items that can be operated in the zone

Items that can be operated in the zone are as follows.

Zone operable item list

Item

Overview

Action

Create Zone

The zone is created and registered.

Customer Portal / API

Change Description

Change the description registered in the zone.

Customer Portal / API

Delete Zone

The registered zone will be deleted.
NOTE: Deleting a zone will delete all record sets that were set in the target zone.
NOTE: Please be careful because delete zones can not restored or referred.

Customer Portal / API


10.2.3.2. Recordset

Setting items when creating a record set

Please set the following items when creating record set in target zone.
After setting various items, pressing the “Create” button creates the record set set for the target zone.

Note

It takes about 5 to 30 seconds for the setting contents of the created record set to be reflected on the name server.

** Setting item list when creating a record set **

Items

Settings

Details

Action

Create record set

Name
Enter the domain name to be registered in the resource record with FQDN.
NOTE: Only single-byte alphanumeric characters can be entered. Japanese input is not possible.

Customer Portal / API

  Type
Please select the resource record type from the following.
  • “A – IPv4 address”
  • “CNAME – Canonical name”
  • “MX – Mail exchange”
  • “AAAA – IPv6 address”
  • “TXT – Text”
  • “SRV – Service locator”
  • “SPF – Sender Policy Framework”
  • “PTR - Pointer”
  • “NS - Name server”

Customer Portal / API

  TTL (Seconds)

Set cache hold time (TTL). It is possible to set an arbitrary integer value in seconds. It is also possible to select from 1 m (1 min), 5 m (5 min), 1 h (1 hour), 1 d (1 day).

Customer Portal / API

  Value
Please enter a value corresponding to the specified Type.
(Example) When “A - IPv4 address” is selected for Type, enter “192.0.2.235”.

Customer Portal / API

  Description
It is possible to enter arbitrary comments in the record set to be set.
Up to 255 characters can be entered with single byte alphanumeric symbols (* 1).
API

NOTE: Available alphanumeric characters are as follows: abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVwXYZ0123456789!”#$%&’()*+,-./:;<=>?@[]^_`{|}~


Items that can be operated on record set

Items that can be operated with record set are as follows.

** Setting item list when creating a record set **

Item

Overview

Action

Create record set

Create a record set in the target zone and register it.

Customer Portal / API

Edit record set

The following items of registered record set will be changed. * Name * TTL (Seconds) * Value * Description

Customer Portal / API

Delete record set

The registered record set will be deleted.
NOTE: Please be careful because the deleted record set can not be restored or referred.

Customer Portal / API


10.2.4. Menu Plan

10.2.4.1. List of Menu

The menu provided in the DNS menu is as follows.

Menu List of the DNS menu

Menu

Provided functions

DNS

Zone

 

Recordset


10.2.4.2. Plan List

There is no preparation of multiple plans in the DNS menu.


10.2.4.3. Subscription Methods

Application for using the DNS menu itself is unnecessary. After creating a tenant, you can use it by creating zones and record sets.

Charges will be made according to the created records.


10.2.5. Terms And Conditions

10.2.5.1. Conditions of Usage with Other Menus

The DNS menu does not restrict special combinations with other menus.
It is possible to mainly combine with the following menu.

Example of combination with other menu

Menu

Use Case for Combination with Virtual Server Menu

Baremetal Server

By linking the address set for the bare metal server with the host name of the customer domain,

It is possible to create an Internet public web server that can be accessed by the host name of the customer domain.

Virtual Server

By linking the address set for the virtual server with the host name of the customer domain,

It is possible to create an Internet public web server that can be accessed by the host name of the customer domain.

Loadbalancer

By linking the host name of the load balancer and the host name of the customer domain and placing multiple resources under the load balancer,

It is possible to build an Internet public Web server that can be accessed by the load balancer loading host name of the customer domain.


10.2.5.2. Minimum Usage Period

Minimum usage period is not set in this menu.


10.2.5.3. Precautions before use

Support Coverage

This menu provides support with following coverage:

  • Operation screen provided by DNS, usage of API · Inquiries on specifications,

  • Functions provided in DNS, operation screen, API breakdown, bug


Notes

  • Since the DNS server provided in this menu is published on the Internet and shared by multiple customers, the DNS zone information created by the customer may be visible from a third party. The result of retrieving information not included in the zone created by the customer is undefined.

  • Since it is not a domain registrar service, there is no domain name registration function. In order to make the DNS zone created in this menu available from the whole Internet, it is necessary to register the corresponding domain name separately in the domain registrar service and register the DNS server name provided in this menu as name server information.

  • Name server information is provided in host name. Actual IP address may change. Always use the host name when designating a name server.

  • If the customer’s data saved in this menu is lost, damaged or leaked, or is used for purposes other than the original purpose due to loss, damage, leakage or other reasons,
    As a result, we will not assume any responsibility for any direct or indirect damage caused to customers or third parties regardless of the cause.
  • We may suspend and delete customers’ use services if we determine that customer’s settings based on this menu are malicious or to have a negative impact on NTT Com and third parties.

  • NTT Com will terminate Customers’ stored data located in this Service Menu in the event that Customers terminate the contract they signed with NTT Com.

  • NTT Com reserves a right to terminate or erase the Customers’ subscription of this menu in the event that NTT Com determines or has the suspicion that Customers breach any Terms and Conditions of this menu or any other policies.

  • This menu is a service that multiple name servers are shared by multiple customers. There is a possibility to take measures such as limiting the use of customers when there is a high possibility that the query for the record of a specific host is remarkably high and the operation of the service and the use of other customers may be affected.

  • This menu provides following support:
    • Infrastructure of this menu is monitored 24/7.

    • Maintenance and troubleshooting are provided based on the details on Support menu described in other documents.

    • Other qualities of operation will correspond to the degree of such where NTT Com defines as its standard operation and terms of service for Enterprise cloud 2.0.
      Enterprise Cloud 2.0 Service Descriptions Support
  • In this menu, the following conditions will be broken down and will be notified to customers according to the method specified separately.
    • When all name servers in the name server group containing the target zone setting do not respond to the request
      (Except when some name server in the name server group responds)
    • Portal / API: Failure affecting customers (inoperability etc.)

  • Following events are not regarded as failures:
    • Inoperable difficulty due to Network (or Internet) misuse or mishaps

    • Quality Deterioration.


10.2.5.4. Restrictions

On the relationship between DNS menu and tenant

Note

Although this menu can be used from any tenant in any region, information (zone, record set) set in this menu can only be viewed, edited and deleted from the tenant from the setting source.
Please note that you can not view, edit, or delete DNS configuration information of other tenants even within the same contract or the same region. Information registered in the name server can be viewed.
(Example) If you use this menu with the tenant a1 in Region A, create a zone for example.com, and register the record set,
It is not possible to view, edit, or delete the contents of zones or record sets of example.com from tenant b1 in region B or tenant a2 in region A.

Zone restrictions

There are the following constraints in the zone setting.

Zone restrictions

Items

Restrictions

Details

Domain name of the zone

Up to 3 same zones can be registered

As long as there are unconfigured name server groups, up to 3 same zones can be registered.
(Supplement) About name server group when registering same zone
If you set a zone that has already been set up (including other tenants and other contracts), the applicable zone of the already set zone
A name server group different from the name server group is assigned to that zone.

Note

(Reference) Subdomain setting of domain hosted on external DNS
It is also possible to use delegation of delegation to the DNS of this menu for subdomains of domains hosted on external DNS outside this menu.

Restrictions on Record set

There are the following constraints on setting of record set.

Record set constraint

Items

Restrictions

Details

Reverse setting

Only global IP addresses used within the same contract can be set

The reverse lookup setting for the global IP address of this service can be set only for the global IP address used within the same contract.
Reverse setting can not be set for the global IP address or unused global IP address used in another contract.
There is a time when it is not possible to reverse the setting for up to 30 minutes immediately after adding the global IP address in the tenant.
If you cancel (return) the global IP address you are setting up reverse lookup, the reverse response for the global IP address will be reset to the default value.
However, the reverse lookup setting itself is not automatically deleted, so delete the reverse lookup setting if it is not necessary.
(If the zone concerning the reverse drawing setting remains, the charge of the zone will continue to occur, so please be careful)
(Reference) Reverse setting regarding the global IP address of this service can be set only in this menu. (It can not be set with other DNS service)

Note

(Reference) Settings related to the IP address used outside this service

  • For forward lookup settings, you can also set global IP addresses used outside of this service.
  • For the reverse lookup setting, you can also set the global IP address used outside this service, but it is necessary to delegate authority from the provider of the global IP address to the name server of this menu.
    For authority delegation please contact the provider of the global IP address.

Uppermost Maximum Capacity for Utilization

In this menu, the maximum number of usage is set as follows.

Maximum number of DNS menus available

Items

 

Restrictions

Details

Zone

Number of zones

100 Zones

The maximum number of zones that can be set in 1 tenant’s DNS menu is 100 zones.

Recordset

Number of Record Sets

1,000 records

The maximum number of record sets that can be set in one zone is 1,000 records.

  TTL

0~86400 seconds

The settable cache storage time (TTL) is an integer value between 0 and 86400 seconds.

The default is 60 seconds.


10.2.6. Pricing

10.2.6.1. Initial Fee

Initial cost is unnecessary in the DNS menu.


10.2.6.2. Monthly Fee

In the DNS menu, we calculate the monthly fee according to the number of zones used as follows.

Items

Details

Number of zones

Monthly fee will be applied in 5 zone units for the zone used for the current month.


10.2.7. SLA of the DNS Menu

10.2.7.1. SLA

The SLA of this menu conforms to the SLA standard defined for this service. For details, refer to the following page.

Enterprise Cloud 2.0 Service Description: SLA

Note

  • In the DNS menu, the case where all name servers in the name server group of the target zone did not respond to the request is defined as the failure time.

Please be careful, in the following cases it is not included in the failure time.

  • When there is a response from a partial name server in the name server group

  • Reduce response capability of name server

  • Failure to create, edit, or delete zones or record sets

  • Failure of Customer Portal/API.