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VMware Solutions DNS configuration

VMware Solutions DNS configuration

Collecting Active Directory credentials

  1. Log in to IBM Cloud®.
  2. From the left menu, select VMware.
  3. From the IBM Cloud for VMware Solutions console, click Resources > vCenter Server from the left navigation pane.
  4. Select your deployed instance.
  5. Click the Access information tab and collect the AD/DNS IP and remote desktop credentials.
  6. From a jump server or by using SSL VPN, remote desktop to the AD/DNS server.

Creating DNS records

  1. Based on the following example, create a table to record your values.
  2. Update the following PowerShell commands with your values.
  3. From the Windows® RDP Session, open a PowerShell command window.
  4. Run commands to create the DNS artifacts.
    • Reverse Lookup Zones
    • Create DNS A Records with PTR
    • Create DNS Service record for etcd
    • Create DNS SRV record for etcd

Notes about DNS records

  • The Add-DnsServerPrimaryZone-networkid cmdlet creates only classful reverse lookup zones. Therefore, if you specify a prefix longer than /24, then the cmdlet creates a /32 reverse lookup zone. Therefore, as a workaround in the script use /24 instead of a /26. You also need to modify the private portable subnet to match the classful /24 network in the commands.
  • Do not create CNAME entries because the Red Hat® OpenShift® certificates are keyed to the DNS returning the IP address only and not a referral to the base hostname. Use the following format for DNS naming standards: HostName.ClusterName.SubDomain.DomainName
    • HostName - Name of the virtual machine or host, for example, control-plane-0
    • ClusterName - Red Hat OpenShift cluster name, for example, ocp
    • SubDomain - Subdomain of the IBM Cloud for VMware Solutions deployment, for example, dallas
    • DomainName - Domain name of the IBM Cloud for VMware Solutions Deployment, for example, ibm.local

For example, the FQDN would be, control-plane-0.ocp.dallas.ibm.local.

The following table is for an example deployment. Use your own values.

DNS records for OpenShift implementation
DNS Description DNS Example Name DNS Example IP address
DNS Reverse Lookup for Red Hat OpenShift VXLAN 192.168.133.0/24
DNS Reverse Lookup for Red Hat OpenShift IBM Cloud Subnet 10.208.242.128/26
Bastion Host bastion.ocp.dallas.ibm.local 192.168.133.8
bootstrap-0 Host bootstrap-0.ocp.dallas.ibm.local 192.168.133.9
control-plane-0 Host control-plane-0.ocp.dallas.ibm.local 192.168.133.10
control-plane-1 Host control-plane-1.ocp.dallas.ibm.local 192.168.133.11
control-plane-2 Host control-plane-2.ocp.dallas.ibm.local 192.168.133.12
compute-0 Host compute-0.ocp.dallas.ibm.local 192.168.133.13
compute-1 Host compute-1.ocp.dallas.ibm.local 192.168.133.14
compute-2 Host compute-2.ocp.dallas.ibm.local 192.168.133.15
Application wildcard DNS (Load Balancer) *.apps.ocp.dallas.ibm.local 10.208.242.131
Kubernetes API URL (Load Balancer) api.ocp.dallas.ibm.local 10.208.242.132
Kubernetes API-INT (Internal) URL (Load Balancer) api-int.ocp.dallas.ibm.local 10.208.242.132
etcd Node0 etcd-0.ocp.dallas.ibm.local 192.168.133.10
etcd Node1 etcd-1.ocp.dallas.ibm.local 192.168.133.11
etcd Node2 etcd-2.ocp.dallas.ibm.local 192.168.133.12
etcd Service Record Node 0 _etcd-server-ssl._tcp.ocp.dallas.ibm.local 192.168.133.10
etcd Service Record Node 1 _etcd-server-ssl._tcp.ocp.dallas.ibm.local 192.168.133.11
etcd Service Record Node 2 _etcd-server-ssl._tcp.ocp.dallas.ibm.local 192.168.133.12

DNS commands

# Create Reverse Lookup Zones
Add-DnsServerPrimaryZone -networkid "192.168.133.0/24" -replicationscope forest
Add-DnsServerPrimaryZone -networkid "10.208.242.0/24" -replicationscope forest

# Create DNS A Records, with PTR
Add-DnsServerResourceRecordA -Name "bastion.ocp.dallas" -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "192.168.133.8" -CreatePtr -TimeToLive 00:00:10
Add-DnsServerResourceRecordA -Name "bootstrap-0.ocp.dallas" -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "192.168.133.9" -CreatePtr -TimeToLive 00:00:10
Add-DnsServerResourceRecordA -Name "control-plane-0.ocp.dallas" -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "192.168.133.10" -CreatePtr -TimeToLive 00:00:10
Add-DnsServerResourceRecordA -Name "etcd-0.ocp.dallas" -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "192.168.133.10" -TimeToLive 00:00:10
Add-DnsServerResourceRecordA -Name "control-plane-1.ocp.dallas" -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "192.168.133.11" -CreatePtr -TimeToLive 00:00:10
Add-DnsServerResourceRecordA -Name "etcd-1.ocp.dallas" -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "192.168.133.11" -TimeToLive 00:00:10
Add-DnsServerResourceRecordA -Name "control-plane-2.ocp.dallas"  -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "192.168.133.12" -CreatePtr -TimeToLive 00:00:10
Add-DnsServerResourceRecordA -Name "etcd-2.ocp.dallas" -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "192.168.133.12" -TimeToLive 00:00:10
Add-DnsServerResourceRecordA -Name "compute-0.ocp.dallas" -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "192.168.133.13" -CreatePtr -TimeToLive 00:00:10
Add-DnsServerResourceRecordA -Name "compute-1.ocp.dallas" -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "192.168.133.14" -CreatePtr -TimeToLive 00:00:10
Add-DnsServerResourceRecordA -Name "compute-2.ocp.dallas" -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "192.168.133.15" -CreatePtr -TimeToLive 00:00:10
Add-DnsServerResourceRecordA -Name "*.apps.ocp.dallas" -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "10.208.242.131" -CreatePtr -TimeToLive 00:00:10
Add-DnsServerResourceRecordA -Name "api.ocp.dallas" -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "10.208.242.132" -CreatePtr -TimeToLive 00:00:10
Add-DnsServerResourceRecordA -Name "api-int.ocp.dallas" -ZoneName "ibm.local" -AllowUpdateAny -IPv4Address "10.208.242.132" -CreatePtr -TimeToLive 00:00:10

# Create DNS SRV record for etcd
Add-DnsServerResourceRecord -Srv -ZoneName "ibm.local" -Name "_etcd-server-ssl._tcp.ocp.dallas" -DomainName "etcd-0.ocp.dallas.ibm.local"  -Priority 10 -Weight 0 -Port 2380
Add-DnsServerResourceRecord -Srv -ZoneName "ibm.local" -Name "_etcd-server-ssl._tcp.ocp.dallas" -DomainName "etcd-1.ocp.dallas.ibm.local"  -Priority 10 -Weight 0 -Port 2380
Add-DnsServerResourceRecord -Srv -ZoneName "ibm.local" -Name "_etcd-server-ssl._tcp.ocp.dallas" -DomainName "etcd-2.ocp.dallas.ibm.local"  -Priority 10 -Weight 0 -Port 2380