5.2

View waits a maximum of five minutes for a desktop to start. If the start time takes longer, other errors are
likely to occur. To be conservative, you can set a concurrent power operations limit of 5 times the peak
power-on rate. With a conservative approach, the default setting of 50 supports a peak power-on rate of 10
desktops per minute.
Logons, and therefore desktop power on operations, typically occur in a normally distributed manner over a
certain time window. You can approximate the peak power-on rate by assuming that it occurs in the middle
of the time window, during which about 40% of the power-on operations occur in 1/6th of the time window.
For example, if users log on between 8:00 AM and 9:00 AM, the time window is one hour, and 40% of the
logons occur in the 10 minutes between 8:25 AM and 8:35 AM. If there are 2,000 users, 20% of whom have
their desktops powered off, then 40% of the 400 desktop power-on operations occur in those 10 minutes. The
peak power-on rate is 16 desktops per minute.
Accept the Thumbprint of a Default SSL Certificate
When you add vCenter Server and View Composer instances to Horizon View, you must ensure that the
SSL certificates that are used for the vCenter Server and View Composer instances are valid and trusted by
View Connection Server. If the default certificates that are installed with vCenter Server and View
Composer are still in place, you must determine whether to accept these certificates' thumbprints.
If a vCenter Server or View Composer instance is configured with a certificate that is signed by a CA, and
the root certificate is trusted by View Connection Server, you do not have to accept the certificate
thumbprint. No action is required.
If you replace a default certificate with a certificate that is signed by a CA, but View Connection Server does
not trust the root certificate, you must determine whether to accept the certificate thumbprint. A thumbprint
is a cryptographic hash of a certificate. The thumbprint is used to quickly determine if a presented certificate
is the same as another certificate, such as the certificate that was accepted previously.
NOTE If you install vCenter Server and View Composer on the same Windows Server host, they can use the
same SSL certificate, but you must configure the certificate separately for each component.
For details about configuring SSL certificates, see Chapter 7, “Configuring SSL Certificates for View
Servers,” on page 71.
You first add vCenter Server and View Composer in View Administrator by using the Add vCenter Server
wizard. If a certificate is untrusted and you do not accept the thumbprint, you cannot add vCenter Server
and View Composer.
After these servers are added, you can reconfigure them in the Edit vCenter Server dialog box.
NOTE You also must accept a certificate thumbprint when you upgrade from an earlier release to
Horizon View 5.1 or later, and a vCenter Server or View Composer certificate is untrusted, or if you replace
a trusted certificate with an untrusted certificate.
On the View Administrator dashboard, the vCenter Server or View Composer icon turns red and an Invalid
Certificate Detected dialog box appears. You must click Verify and follow the procedure shown here.
Similarly, in View Administrator you can configure a SAML 2.0 authenticator for use by a View Connection
Server instance. If the SAML 2.0 server certificate is not trusted by View Connection Server, you must
determine whether to accept the certificate thumbprint. If you do not accept the thumbprint, you cannot
configure the SAML 2.0 authenticator in Horizon View. After a SAML 2.0 authenticator is configured, you
can reconfigure it in the Edit View Connection Server dialog box.
Procedure
1 When View Administrator displays an Invalid Certificate Detected dialog box, click View Certificate.
2 Examine the certificate thumbprint in the Certificate Information window.
VMware Horizon View Installation
102 VMware, Inc.