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Manage DNS records and recordsets in Azure DNS using Azure PowerShell

This article shows you how to manage DNS records for your DNS zone by using Azure PowerShell. DNS records can also be managed by using the cross-platform Azure CLI or the Azure portal.

The examples in this article assume you have already installed Azure PowerShell, signed in, and created a DNS zone.

Note

We recommend that you use the Azure Az PowerShell module to interact with Azure. To get started, see Install Azure PowerShell. To learn how to migrate to the Az PowerShell module, see Migrate Azure PowerShell from AzureRM to Az.

Introduction

Before creating DNS records in Azure DNS, you first need to understand how Azure DNS organizes DNS records into DNS record sets.

Record names

In Azure DNS, records are specified by using relative names. A fully qualified domain name (FQDN) includes the zone name, whereas a relative name doesn't. For example, the relative record name www in the zone contoso.com gives the fully qualified record name www.contoso.com.

An apex record is a DNS record at the root (or apex) of a DNS zone. For example, in the DNS zone contoso.com, an apex record also has the fully qualified name contoso.com (this is sometimes called a naked domain). By convention, the relative name '@' is used to represent apex records.

Record types

Each DNS record has a name and a type. Records are organized into various types according to the data they contain. The most common type is an 'A' record, which maps a name to an IPv4 address. Another common type is an 'MX' record, which maps a name to a mail server.

Azure DNS supports all common DNS record types: A, AAAA, CAA, CNAME, MX, NS, PTR, SOA, SRV, and TXT. Note that SPF records are represented using TXT records.

Additional record types are supported if the zone is signed with DNS Security Extensions (DNSSEC), such as Delegation Signer (DS) and Transport Layer Security Authentication (TLSA) resource records.

DNSSEC resource record types such as DNSKEY, RRSIG, and NSEC3 records are added automatically when a zone is signed with DNSSEC. These types of DNSSEC resource records can't be created or modified after zone signing.

Record sets

Sometimes you need to create more than one DNS record with a given name and type. For example, suppose the 'www.contoso.com' web site is hosted on two different IP addresses. The website requires two different A records, one for each IP address. Here's an example of a record set:

www.contoso.com.        3600    IN    A    134.170.185.46
www.contoso.com.        3600    IN    A    134.170.188.221

Azure DNS manages all DNS records using record sets. A record set (also known as a resource record set) is the collection of DNS records in a zone that have the same name and are of the same type. Most record sets contain a single record. However, examples like the one above, in which a record set contains more than one record, aren't uncommon.

For example, suppose you have already created an A record 'www' in the zone 'contoso.com', pointing to the IP address '134.170.185.46' (the first record above). To create the second record you would add that record to the existing record set, rather than create an additional record set.

The SOA and CNAME record types are exceptions. The DNS standards don't permit multiple records with the same name for these types, therefore these record sets can only contain a single record.

For more information about DNS records in Azure DNS, see DNS zones and records.

Create a new DNS record

To create a new record set, it has to have a different name and type than any existing records. If the new record has the same name and type as an existing record, you'll need to add it to the existing record set.

Create 'A' records in a new record set

You create record sets by using the New-AzDnsRecordSet cmdlet. When creating a record set, you need to specify the record set name, the zone, the time to live (TTL), the record type, and the records to be created.

The parameters for adding records to a record set vary depending on the type of the record set. For example, when using a record set of type 'A', you need to specify the IP address using the parameter -IPv4Address. Different record types will have extra parameters.

The following example creates a record set with the relative name www in the DNS Zone contoso.com. The fully qualified name of the record set is www.contoso.com. The record type is 'A', and the TTL is 3600 seconds. The record set contains a single record, with IP address '1.2.3.4'.

New-AzDnsRecordSet -Name "www" -RecordType A -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -Ttl 3600 -DnsRecords (New-AzDnsRecordConfig -IPv4Address "1.2.3.4") 

To create a record set at the 'apex' of a zone (in this case, 'contoso.com'), use the record set name '@' (excluding quotation marks):

New-AzDnsRecordSet -Name "@" -RecordType A -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -Ttl 3600 -DnsRecords (New-AzDnsRecordConfig -IPv4Address "1.2.3.4") 

If you need to create a record set containing more than one record, first create a local array and add the records, then pass the array to New-AzDnsRecordSet as follows:

$aRecords = @()
$aRecords += New-AzDnsRecordConfig -IPv4Address "1.2.3.4"
$aRecords += New-AzDnsRecordConfig -IPv4Address "2.3.4.5"
New-AzDnsRecordSet -Name www –ZoneName "contoso.com" -ResourceGroupName MyResourceGroup -Ttl 3600 -RecordType A -DnsRecords $aRecords

Record set metadata can be used to associate application-specific data with each record set, as key-value pairs. The following example shows how to create a record set with two metadata entries, 'dept=finance' and 'environment=production'.

New-AzDnsRecordSet -Name "www" -RecordType A -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -Ttl 3600 -DnsRecords (New-AzDnsRecordConfig -IPv4Address "1.2.3.4") -Metadata @{ dept="finance"; environment="production" } 

Azure DNS also supports 'empty' record sets, which can act as a placeholder to reserve a DNS name before creating DNS records. Empty record sets are visible in the Azure DNS control plane, but do appear on the Azure DNS name servers. The following example creates an empty record set:

New-AzDnsRecordSet -Name "www" -RecordType A -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -Ttl 3600 -DnsRecords @()

Create records of other types

Having seen in detail how to create 'A' records, the following examples show how to create records of other record types supported by Azure DNS.

In each case, we show how to create a record set containing a single record. The earlier examples for 'A' records can be adapted to create record sets of other types containing multiple records, with metadata, or to create empty record sets.

There's no example for create an SOA record set, since SOAs are created and deleted with each DNS zone. The SOA record can't be created or deleted separately. However, the SOA can be modified, as shown in a later example.

Create an AAAA record set with a single record

New-AzDnsRecordSet -Name "test-aaaa" -RecordType AAAA -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -Ttl 3600 -DnsRecords (New-AzDnsRecordConfig -Ipv6Address "2607:f8b0:4009:1803::1005") 

Create a CAA record set with a single record

New-AzDnsRecordSet -Name "test-caa" -RecordType CAA -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -Ttl 3600 -DnsRecords (New-AzDnsRecordConfig -Caaflags 0 -CaaTag "issue" -CaaValue "ca1.contoso.com") 

Create a CNAME record set with a single record

Note

The DNS standards do not permit CNAME records at the apex of a zone (-Name '@'), nor do they permit record sets containing more than one record.

For more information, see CNAME records.

New-AzDnsRecordSet -Name "test-cname" -RecordType CNAME -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -Ttl 3600 -DnsRecords (New-AzDnsRecordConfig -Cname "www.contoso.com") 

Create an MX record set with a single record

In this example, we use the record set name '@' to create an MX record at the zone apex (in this case, 'contoso.com').

New-AzDnsRecordSet -Name "@" -RecordType MX -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -Ttl 3600 -DnsRecords (New-AzDnsRecordConfig -Exchange "mail.contoso.com" -Preference 5) 

Create an NS record set with a single record

New-AzDnsRecordSet -Name "test-ns" -RecordType NS -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -Ttl 3600 -DnsRecords (New-AzDnsRecordConfig -Nsdname "ns1.contoso.com") 

Create a PTR record set with a single record

In this case, 'my-arpa-zone.com' represents the ARPA reverse lookup zone representing your IP range. Each PTR record set in this zone corresponds to an IP address within this IP range. The record name '10' is the last octet of the IP address within this IP range represented by this record.

New-AzDnsRecordSet -Name 10 -RecordType PTR -ZoneName "my-arpa-zone.com" -ResourceGroupName "MyResourceGroup" -Ttl 3600 -DnsRecords (New-AzDnsRecordConfig -Ptrdname "myservice.contoso.com") 

Create an SRV record set with a single record

When creating an SRV record set, specify the _service and _protocol in the record set name. There's no need to include '@' in the record set name when creating an SRV record set at the zone apex.

New-AzDnsRecordSet -Name "_sip._tls" -RecordType SRV -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -Ttl 3600 -DnsRecords (New-AzDnsRecordConfig -Priority 0 -Weight 5 -Port 8080 -Target "sip.contoso.com") 

Create a TXT record set with a single record

The following example shows how to create a TXT record. For more information about the maximum string length supported in TXT records, see TXT records.

New-AzDnsRecordSet -Name "test-txt" -RecordType TXT -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -Ttl 3600 -DnsRecords (New-AzDnsRecordConfig -Value "This is a TXT record") 

Get a record set

To retrieve an existing record set, use Get-AzDnsRecordSet. This cmdlet returns a local object that represents the record set in Azure DNS.

As with New-AzDnsRecordSet, the record set name given must be a relative name, meaning it must exclude the zone name. You also need to specify the record type, and the zone containing the record set.

The following example shows how to retrieve a record set. In this example, the zone is specified using the -ZoneName and -ResourceGroupName parameters.

$rs = Get-AzDnsRecordSet -Name "www" -RecordType A -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup"

Instead, you can also specify the zone using a zone object, passed using the -Zone parameter.

$zone = Get-AzDnsZone -Name "contoso.com" -ResourceGroupName "MyResourceGroup"
$rs = Get-AzDnsRecordSet -Name "www" -RecordType A -Zone $zone

List record sets

You can also use Get-AzDnsZone to list record sets in a zone, by omitting either or both the -Name or -RecordType parameters.

The following example returns all record sets in the zone:

$recordsets = Get-AzDnsRecordSet -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup"

The following example shows how you can retrieve all record sets of a given type by specifying the record type when omitting the record set name:

$recordsets = Get-AzDnsRecordSet -RecordType A -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup"

To retrieve all record sets with a given name, across record types, you need to retrieve all record sets and then filter the results:

$recordsets = Get-AzDnsRecordSet -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" | where {$_.Name.Equals("www")}

In all the above examples, the zone can be specified either by using the -ZoneName and -ResourceGroupNameparameters (as shown), or by specifying a zone object:

$zone = Get-AzDnsZone -Name "contoso.com" -ResourceGroupName "MyResourceGroup"
$recordsets = Get-AzDnsRecordSet -Zone $zone

Add a record to an existing record set

To add a record to an existing record set, follow the following three steps:

  1. Get the existing record set

    $rs = Get-AzDnsRecordSet -Name www –ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -RecordType A
    
  2. Add the new record to the local record set.

    Add-AzDnsRecordConfig -RecordSet $rs -Ipv4Address "5.6.7.8"
    
  3. Update the changes so it reflects to the Azure DNS service.

    Set-AzDnsRecordSet -RecordSet $rs
    

Using Set-AzDnsRecordSet replaces the existing record set in Azure DNS (and all records it contains) with the record set specified. Etag checks are used to ensure concurrent changes aren't overwritten. You can use the optional -Overwrite switch to suppress these checks.

This sequence of operations can also be piped, meaning you pass the record set object by using the pipe rather than passing it as a parameter:

Get-AzDnsRecordSet -Name "www" –ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -RecordType A | Add-AzDnsRecordConfig -Ipv4Address "5.6.7.8" | Set-AzDnsRecordSet

The examples above show how to add an 'A' record to an existing record set of type 'A'. A similar sequence of operations is used to add records to record sets of other types, replacing the -Ipv4Address parameter of Add-AzDnsRecordConfig with other parameters specific to each record type. The parameters for each record type are the same as the New-AzDnsRecordConfig cmdlet, as shown in other record type examples above.

Record sets of type 'CNAME' or 'SOA' can't contain more than one record. This constraint arises from the DNS standards. It isn't a limitation of Azure DNS.

Remove a record from an existing record set

The process to remove a record from a record set is similar to the process to add a record to an existing record set:

  1. Get the existing record set

    $rs = Get-AzDnsRecordSet -Name www –ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -RecordType A
    
  2. Remove the record from the local record set object. The record that's being removed must be an exact match with an existing record across all parameters.

    Remove-AzDnsRecordConfig -RecordSet $rs -Ipv4Address "5.6.7.8"
    
  3. Commit the change back to the Azure DNS service. Use the optional -Overwrite switch to suppress Etag checks for concurrent changes.

    Set-AzDnsRecordSet -RecordSet $Rs
    

Using the above sequence to remove the last record from a record set doesn't delete the record set, rather it leaves an empty record set. To remove a record set entirely, see Delete a record set.

Similarly to adding records to a record set, the sequence of operations to remove a record set can also be piped:

Get-AzDnsRecordSet -Name www –ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" -RecordType A | Remove-AzDnsRecordConfig -Ipv4Address "5.6.7.8" | Set-AzDnsRecordSet

Different record types are supported by passing the appropriate type-specific parameters to Remove-AzDnsRecordSet. The parameters for each record type are the same as for the New-AzDnsRecordConfig cmdlet, as shown in other record type examples above.

Modify an existing record set

The steps for modifying an existing record set are similar to the steps you take when adding or removing records from a record set:

  1. Retrieve the existing record set by using Get-AzDnsRecordSet.
  2. Modify the local record set object by:
    • Adding or removing records
    • Changing the parameters of existing records
    • Changing the record set metadata and time to live (TTL)
  3. Commit your changes by using the Set-AzDnsRecordSet cmdlet. This replaces the existing record set in Azure DNS with the record set specified.

When you use the Set-AzDnsRecordSet command, Etag checks are used to ensure concurrent changes aren't overwritten. You can use the optional -Overwrite switch to suppress these checks.

To update a record in an existing record set

In this example, we change the IP address of an existing 'A' record:

$rs = Get-AzDnsRecordSet -name "www" -RecordType A -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup"
$rs.Records[0].Ipv4Address = "9.8.7.6"
Set-AzDnsRecordSet -RecordSet $rs

To modify an SOA record

You can't add or remove records from the automatically created SOA record set at the zone apex (-Name "@", including quote marks). However, you can modify any of the parameters within the SOA record (except "Host") and the record set TTL.

The following example shows how to change the Email property of the SOA record:

$rs = Get-AzDnsRecordSet -Name "@" -RecordType SOA -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup"
$rs.Records[0].Email = "admin.contoso.com"
Set-AzDnsRecordSet -RecordSet $rs

To modify NS records at the zone apex

The NS record set at the zone apex is automatically created with each DNS zone. It contains the names of the Azure DNS name servers assigned to the zone.

You can add more name servers to this NS record set, to support cohosting domains with more than one DNS provider. You may also modify the TTL and metadata for this record set. However, you can't remove or modify the pre-populated Azure DNS name servers.

This restriction applies only to the NS record set at the zone apex. Other NS record sets in your zone (as used to delegate child zones) can be modified without constraint.

The following example shows how to add another name server to the NS record set at the zone apex:

$rs = Get-AzDnsRecordSet -Name "@" -RecordType NS -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup"
Add-AzDnsRecordConfig -RecordSet $rs -Nsdname ns1.myotherdnsprovider.com
Set-AzDnsRecordSet -RecordSet $rs

To modify record set metadata

Record set metadata can be used to associate application-specific data with each record set, as key-value pairs.

The following example shows how to modify the metadata of an existing record set:

# Get the record set
$rs = Get-AzDnsRecordSet -Name www -RecordType A -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup"

# Add 'dept=finance' name-value pair
$rs.Metadata.Add('dept', 'finance') 

# Remove metadata item named 'environment'
$rs.Metadata.Remove('environment')  

# Commit changes
Set-AzDnsRecordSet -RecordSet $rs

Delete a record set

Record sets can be deleted by using the Remove-AzDnsRecordSet cmdlet. Deleting a record set also deletes all records within the record set.

Note

You cannot delete the SOA and NS record sets at the zone apex (-Name '@'). Azure DNS created these automatically when the zone was created, and deletes them automatically when the zone is deleted.

The following example shows how to delete a record set. In this example, the record set name, record set type, zone name, and resource group are each specified explicitly.

Remove-AzDnsRecordSet -Name "www" -RecordType A -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup"

Instead, the record set can be specified by name and type, and the zone specified using an object:

$zone = Get-AzDnsZone -Name "contoso.com" -ResourceGroupName "MyResourceGroup"
Remove-AzDnsRecordSet -Name "www" -RecordType A -Zone $zone

As a third option, the record set itself can be specified using a record set object:

$rs = Get-AzDnsRecordSet -Name www -RecordType A -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup"
Remove-AzDnsRecordSet -RecordSet $rs

When you specify the record set to get deleted by using a record set object, Etag checks are used to ensure concurrent changes don't get deleted. You can use the optional -Overwrite switch to suppress these checks.

The record set object can also be piped instead of being passed as a parameter:

Get-AzDnsRecordSet -Name www -RecordType A -ZoneName "contoso.com" -ResourceGroupName "MyResourceGroup" | Remove-AzDnsRecordSet

Confirmation prompts

The New-AzDnsRecordSet, Set-AzDnsRecordSet, and Remove-AzDnsRecordSet cmdlets all support confirmation prompts.

Each cmdlet prompts for confirmation if the $ConfirmPreference PowerShell preference variable has a value of Medium or lower. Since the default value for $ConfirmPreference is High, these prompts aren't given when using the default PowerShell settings.

You can override the current $ConfirmPreference setting using the -Confirm parameter. If you specify -Confirm or -Confirm:$True , the cmdlet prompts you for confirmation before it runs. If you specify -Confirm:$False , the cmdlet doesn't prompt you for confirmation.

For more information about -Confirm and $ConfirmPreference, see About Preference Variables.

Next steps

Learn more about zones and records in Azure DNS.
Learn how to protect your zones and records when using Azure DNS.
Review the Azure DNS PowerShell reference documentation.