Red Hat NETWORK PROXY 5.3.0 -, Руководство по установке

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How it Works
3
Traceback
A traceback is a detailed description of "what went wrong" that is useful for troubleshooting the
RHN Proxy Server. Tracebacks are automatically generated when a critical error occurs and are
emailed to the individual(s) designated in the RHN Proxy Server's configuration file.
For more detailed explanations of these terms and others, refer to the
Red Hat Network Reference
Guide
available at
http://www.redhat.com/docs/manuals/satellite/
and the
Help
page on the Satellite
Web user interface.
1.4. How it Works
The Red Hat Update Agent or
Package Updater
on the client systems does not directly contact a
Red Hat Network Server. Instead, the client (or clients) connects in turn to an RHN Proxy Server that
connects to the Red Hat Network Servers or to a RHN Satellite Server. Thus, the client systems do not
need direct access to the Internet. They need access only to the RHN Proxy Server.
Important
Red Hat strongly recommends that clients connected to an RHN Proxy Server be
running the latest update of Red Hat Enterprise Linux to ensure proper connectivity.
Clients that access RHN directly are authenticated by the RHN servers. Clients that access an
RHN Proxy Server are still authenticated by RHN; however, in this case the Proxy provides both
authentication and route information to RHN. After a successful authentication, the Red Hat Network
Server informs the RHN Proxy Server that it is permitted to execute a specific action for the client. The
RHN Proxy Server downloads all of the updated packages (if they are not already present in its cache)
and delivers them to the client system.
Requests from the Red Hat Update Agent or Package Updater on the client systems are still
authenticated on the server side, but package delivery is significantly faster since the packages are
cached in the HTTP Proxy Caching Server or the RHN Proxy Server (for local packages); the RHN
Proxy Server and client system are connected via the LAN and are limited only by the speed of the
local network.
Authentication is done in the following order:
1. The client performs a login action at the beginning of a client session. This login is passed through
one or more RHN Proxy Servers until it reaches a Red Hat Network Server.
2. The Red Hat Network Server attempts to authenticate the client. If authentication is successful,
the server then passes back a session token via the chain of RHN Proxy Servers. This token,
which has a signature and expiration, contains user information, including channel subscriptions,
username, etc.
3. Each RHN Proxy Server caches this token on its local file system in
/var/cache/rhn/
. Caching
reduces some of the overhead of authenticating with Red Hat Network Servers and greatly
improves the performance of Red Hat Network.
4. This session token is passed back to the client machine and is used in subsequent actions on Red
Hat Network.
From the client's point of view, there is no difference between an RHN Proxy Server and a Red Hat
Network Server. From the Red Hat Network Server's point of view, an RHN Proxy Server is a special