7 synchronized system clocks, 8 insight control for linux ram disk environment, 9 network configuration and dhcp requirements – HP Insight Control Software for Linux User Manual
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1.7 Synchronized system clocks
When using Insight Control for Linux, and especially when using Insight Control for Linux tools to
install operating systems on managed systems, to capture and deploy Linux images, HP recommends
that you keep system clocks up to date and synchronized.
Synchronization is required for the Console Maintenance Facility to access a managed system
using SSH.
Capturing an image from a managed system or deploying an image to a server whose system
time is incorrect can cause a large number of error messages when the image is deployed. These
messages do not affect the deployment, but they can add significant time delays to the deployment.
To avoid this and other problems, always synchronize the clock on the CMS and your managed
systems.
IMPORTANT:
If you decide to implement NTP, make sure the NTP ports are open on your firewall. The default
ports for NTP are UDP:123 and TCP:123.
1.8 Insight Control for Linux RAM disk environment
The Insight Control for Linux
environment is a fully-functioning operating environment in
memory that is used to support discovery, registration, and configuration of HP ProLiant servers
equipped with Integrated Lights Out (
) or, for some servers, LO100i, management processors.
For a list of servers that Insight Control for Linux supports, see the HP Insight Control for Linux
Support Matrix.
The RAM disk's operating environment is enhanced to support HP ProLiant servers and Insight
Control for Linux.
The RAM disk environment is initiated when an HP ProLiant server initiates a network boot (
or
) from a CMS that is installed with the SystemImager Insight Control for Linux boot
RPMs. The operating mode of the RAM disk is determined by kernel command line parameters
passed as part of the PXE boot process.
IMPORTANT:
HP recommends that Insight Control for Linux deployment and capture facilities be
used in a trusted network environment because of inherent insecurity with the PXE boot protocol.
The PXE boot protocol is insecure because of its design. The CMS cannot verify the identity of a
system booting into the RAM disk. Also, the booting managed system cannot verify the identity of
the host from which it receives the RAM disk.
Virtual media is provided as a secure alternative to PXE.
1.9 Network configuration and DHCP requirements
Supported network configurations and
requirements are documented in the HP Insight Control
for Linux Installation Guide.
You can use the virtual media mechanism (see
) as a simpler and more
secure alternative to PXE booting. However, to use virtual media, network parameters must be
configured and applied with the Define Networks and Network Configuration Editor tools. For
information on these tools, see
.
1.10 Virtual media
Virtual media is a mechanism that allows a server with an iLO-based management processor to
boot a Virtual CD (that is, a bootable ISO image) over the network in much the same way that it
would be loaded from a CD or DVD. Virtual media is a secure alternative to PXE. Commands are
sent to the management processor to specify where the ISO image can be found on the CMS.
1.7 Synchronized system clocks
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