Installation and Setup Guide

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Has the certicate expired, or is it valid only in the future? That is, is the certicate valid according to
the computer clock?
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Does the common name on the certicate match the host name of the server that sends it? A mismatch
can occur if a load balancer redirects Horizon Client to a server that has a certicate that does not match
the host name entered in Horizon Client. Another reason a mismatch can occur is if you enter an IP
address rather than a host name in the client.
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Is the certicate signed by an unknown or untrusted certicate authority (CA)? Self-signed certicates
are one type of untrusted CA.
To pass this check, the certicate's chain of trust must be rooted in the device's local certicate store.
N For information about distributing a self-signed root certicate that users can install on their Linux
client systems, see the Ubuntu documentation.
Horizon Client uses the PEM-formaed certicates stored in the /etc/ssl/certs directory on the client
system. For information about importing a root certicate stored in this location, see "Importing a Certicate
into the System-Wide Certicate Authority Database" in the document at
hps://help.ubuntu.com/community/OpenSSL.
In addition to presenting a server certicate, the server also sends a certicate thumbprint to Horizon Client.
The thumbprint is a hash of the certicate public key and is used as an abbreviation of the public key. If the
server does not send a thumbprint, you see a warning that the connection is untrusted.
If your Horizon administrator has allowed it, you can set the certicate checking mode. To set the certicate
checking mode, start Horizon Client and select File > Preferences from the menu bar. You have three
choices:
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Never connect to untrusted servers. If any of the certicate checks fails, the client cannot connect to the
server. An error message lists the checks that failed.
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Warn before connecting to untrusted servers. If a certicate check fails because the server uses a self-
signed certicate, you can click Continue to ignore the warning. For self-signed certicates, the
certicate name is not required to match the server name you entered in Horizon Client.
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Do not verify server identity . This seing means that no certicate checking occurs.
Chapter 3 Managing Remote Desktop and Application Connections
VMware, Inc. 57