In order to troubleshoot issues in VMware you often need to SSH to the host. In older versions of VMware, SSH used to be enabled all the time. Since version 4 you have had to enable it each time you want to use it. However today I came across an ESXi 5.5 host that I could not SSH to despite SSH being started in Security.
To fix the problem I connected to the server via its iDRAC / iLO. Then I checked to see if the firewall ports were open.
esxcli network firewall ruleset list
Look for the value of false next to sshServer.
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If the value is false then the ports are blocked on the ESXi host. We now need to enable these.
esxcli network firewall ruleset set -r sshServer -e true
Querying the firewall rule set now shows this value is true. SSH now works again.
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