While connecting to Vcenter Server Appliance with ssh command I was facing error Too many authentication failures disconnect. I checked ssh settings on the VCSA photon os from VM console but didnt find any issue. 

Related Article: Resetting root password in Vmware Vcenter Server Appliance

ssh root@fqdn_or_ip

VMware vCenter Server x.x.x.xxxxx

Type: vCenter Server with an embedded Platform Services Controller

root@fqdn_or_ip's password:
Received disconnect from fqdn_or_ip port 22:2: Too many authetication failures
Disconnected from fqdn_or_ip port 22

Finally to resolve this issue I created a file config under C:\Users\Profile\.ssh folder and added below entries for my vCenter Server. Specifically the IdentitiesOnly to yes. You can find the below url about ssh_config for more details.

# Read more about SSH config files: https://linux.die.net/man/5/ssh_config
Host vCenter_or_IP
  Hostname vCenter_or_IP
  IdentitiesOnly yes

Next when you try to connect through ssh.exe command use additional parameter -o PubkeyAuthentication=no. As you can see login is successful.

ssh -o PubkeyAuthentication=no root@fqdn_or_ip

VMware vCenter Server x.x.x.xxxxx

Type: vCenter Server with an embedded Platform Services Controller

root@fqdn_or_ip's password:
Connected to service

    * List APIs: "help api list"
    * List Plugins: "help pi list"
    * Launch BASH: "shell"

Command> shell
Shell access is granted to root

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