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Azure load balancer health probe not working

LoganIN 61 Reputation points
2020-09-12T19:09:39.423+00:00

Hello,

I’m using the basic lb for my iis based vms. My lb configuration is,

IIS based website listening on port 80 and same is working with lb as well.

Health probe configured to check port TCP 445 on both the servers.

Load balance configured both front and backend port is 80 and associated the probe rule.

Now, the miracle is website automatically redirects to vm-2 even after I have stopped the website from the vm-1. As I have health probe configured to check only 445, how it’s redirecting to other vm?

I don’t see any article which says it will also check the respective port from lb rule, so It would be helpful if anyone help me with the details how & why? Thank you

Azure Load Balancer
Azure Load Balancer
An Azure service that delivers high availability and network performance to applications.
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  1. TravisCragg-MSFT 5,681 Reputation points Microsoft Employee
    2020-09-15T01:00:56.847+00:00

    To start, the port for HTTPS is 443, not 445. 445 is used for NTFS (file shares).

    If your website does not use HTTPS and only uses HTTP (port 80), then you should use TCP port 80 for your health probe.

    I am unsure how it is sending requests to VM2, but if you are not using HTTPS stick to port 80 for probes.

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