Clavister cOS Core Administration Guide

Chapter 2: Management and Maintenance
When running cOS Core under a VMware server, upgrades of cOS Core can be done just as they
are done on a single physical computer. It is not necessary to create a new virtual machine for a
new version.
Checking the Dynamic High Buffers Setting
Make sure that the advanced setting Dynamic High Buffers is enabled after an upgrade. This
setting ensures that sufficient memory is allocated for handling connections.
This setting requires a hardware restart for a new value to take effect. A reconfiguration is not
sufficient. This can be achieved using the CLI command:
Device:/> shutdown
Where cOS Core is handling tens of thousands of simultaneous connections then it may be
necessary to manually set a value above the automatic value. However, if the HighBuffers value is
set too high this may impact throughput latency.
New Release Notifications
Clavister maintains an RSS feed of announcements that can be subscribed to at:
https://forums.clavister.com/rss-feeds/announcements/.
It is recommended to subscribe to this feed in order to receive notifications when new releases
of cOS Core versions are available for download and installation. Alternatively, announcements
can be read directly from the Clavister forums which can be found at:
https://forums.clavister.com/.
2.6.2. Auto-Update Mechanism
A number of the cOS Core security features rely on external servers for automatic updates and
content filtering. The Intrusion Prevention and Detection system and Anti-Virus modules require
access to updated signature databases in order to provide protection against the latest threats.
To facilitate the Auto-Update feature Clavister maintains a global infrastructure of servers
providing update services for Clavister Security Gateways. To ensure availability and low
response times, cOS Core employs a mechanism for automatically selecting the most
appropriate server to supply updates.
For more details on these features see the following sections:
• Section 6.5, “Intrusion Detection and Prevention”
• Section 6.4, “Anti-Virus Scanning”
• Section 6.3, “Web Content Filtering”
• Appendix A, Update Subscriptions
2.6.3. Backing Up Configurations
The administrator has the ability to take a snapshot of a cOS Core system at a given point in time
and restore it when necessary. The snapshot can be of two types:
• A Configuration Backup
104