README
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Red Hat release 6.1 includes the initial version of Piranha. With this
software, you can build and administer a two-node cluster suitable for
providing highly available Web and FTP services.

The components of Piranha are described below.

LVS

Piranha is based on Wensong Zhang's Linux Virtual Server (LVS) kernel 
routing patch. This component provides for:  

* Building virtual servers: floating IP addresses where requests for service
arrive from the public internet.

* Routing service requests from virtual servers to a pool of real Web and FTP
servers on a private network. 

* Migrating floating IP addresses and routing services from a failed primary
node to a backup node.

* Load-balancing: round robin, weighted round robin, and weighted 
least-busy algorithms are supported.

* Packet-forwarding. The current implementation supports masquerading (NAT)
only, but Wensong's software supports direct routing and IP encapsulation
(tunneling) as well as masquerading.

* TCP or UDP connections, and persistence.

lvs

The lvs daemon runs on the primary and backup nodes. This process controls
Piranha and supports communication among its components.

/etc/lvs.cf

This is the configuration file that, on startup, the lvs daemon reads.

pulse

The pulse daemon runs on the primary and backup nodes. Through this process,
the backup cluster node determines whether the primary node is alive. 

/etc/rc.d/init.d/pulse

This is the pulse startup script.

nanny

The nanny daemon runs on each real Web/FTP server host. Through this process,
the primary LVS node determines whether a host is alive and should continue
to receive job assignments.

ipvsadm

The command line tool for setting up and administering an LVS cluster.

Piranha

The GUI tool for monitoring, configuring, and administering an LVS cluster.
Normally this is the tool you should use to maintain /etc/lvs.cf, 
reconfigure the running daemons, and synchronize files between primary and
backup nodes.

Documentation: lvs.cf(5), lvs(8) ipvsadm(8), pulse(8), HOWTO (??name). 

