Azure-docs: Explicit clarification about coexisting with Public Facing Load Balancer

[SamirFarhat]

Hi,
We all know that any outbound traffic from a VM behind an internet facing load balancer (standard) will be Source-Nated through the LB Public IP.
What happens in case of existence? Which service will prevail? NAT gateway or LB?
Thanks

---

Document Details

⚠ Do not edit this section. It is required for docs.microsoft.com ➟ GitHub issue linking.

• ID: bdb766d9-18ab-2998-d769-99e95ffd8ef8
• Version Independent ID: 467c1ece-0d09-14de-4bda-e3b56d99d546
• Content: What is Azure Virtual Network NAT?
• Content Source: articles/virtual-network/nat-overview.md
• Service: virtual-network
• GitHub Login: @asudbring
• Microsoft Alias: allensu

[BhargaviAnnadevara-MSFT]

@SamirFarhat Thanks for the question! We're investigating this and will get back to you shortly.

[saif-chaudhry]

I would assume NAT Gateway takes precedence here based on this "All outbound traffic for the subnet is processed by NAT automatically without any customer configuration. User-defined routes aren't necessary. NAT takes precedence over other outbound scenarios and replaces the default Internet destination of a subnet."

[christiankuhtz]

Correct. NAT takes precedence over other outbound scenarios.

[christiankuhtz]

this is also explained in detail at https://docs.microsoft.com/en-us/azure/virtual-network/nat-gateway-resource

[SamirFarhat]

Thanks. It's the first time in history an outbound traffic takes precedence over the LB 😆

KR.
Samir Farhat

---

From: Christian Kuhtz [e-mail]
Sent: Tuesday, March 3, 2020 6:22:58 PM
To: MicrosoftDocs/azure-docs [e-mail]
Cc: Samir Farhat (MVP) [e-mail]; Mention [e-mail]
Subject: Re: [MicrosoftDocs/azure-docs] Explicit clarification about coexisting with Public Facing Load Balancer (#49236)

this is also explained in detail at https://docs.microsoft.com/en-us/azure/virtual-network/nat-gateway-resource

—
You are receiving this because you were mentioned.
Reply to this email directly, view it on GitHubhttps://github.com/MicrosoftDocs/azure-docs/issues/49236?email_source=notifications&email_token=ADR7DAAVLF5SNGKCP3HRGMTRFU4HFA5CNFSM4K7E5AA2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOENUMGSY#issuecomment-594068299, or unsubscribehttps://github.com/notifications/unsubscribe-auth/ADR7DAGYQJ5A4CNWWZGEXATRFU4HFANCNFSM4K7E5AAQ.

[christiankuhtz]

Not really ;-) public IP address resources used as instance-level public IP have always done that ;-).. there's already an existing order of precedence captured in https://aka.ms/lboutbound and NAT gateway builds on that notion and offers coexistence with inbound on the same subnet.

[SamirFarhat]

That was a joke 😋
We no longer see you on Azure Advisors. Where have you been?

KR.
Samir Farhat

---

From: Christian Kuhtz [e-mail]
Sent: Tuesday, March 3, 2020 9:01:36 PM
To: MicrosoftDocs/azure-docs [e-mail]
Cc: Samir Farhat (MVP) [e-mail]; Mention [e-mail]
Subject: Re: [MicrosoftDocs/azure-docs] Explicit clarification about coexisting with Public Facing Load Balancer (#49236)

Not really ;-) public IP address resources used as instance-level public IP have always done that ;-).. there's already an existing order of precedence captured in https://aka.ms/lboutbound and NAT gateway builds on that notion and offers coexistence with inbound on the same subnet.

—
You are receiving this because you were mentioned.
Reply to this email directly, view it on GitHubhttps://github.com/MicrosoftDocs/azure-docs/issues/49236?email_source=notifications&email_token=ADR7DAAZBOEX2ESQSG3KAETRFVO2BA5CNFSM4K7E5AA2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOENU56NA#issuecomment-594140980, or unsubscribehttps://github.com/notifications/unsubscribe-auth/ADR7DAHKOZ5A2E3HI2RDDCTRFVO2BANCNFSM4K7E5AAQ.

[christiankuhtz]

Busy building this ;-) @anavinahar owns LB now.