Installation guide

Warning
Do not use the ifup scripts to bring up any floating IP addresses you may configure
using Piranha Configuration Tool (eth0:1 or eth1:1). Use the service command
to start pulse instead (see Section 4.8, “Starting LVS” for details).
Bringing Down Real Network Interfaces
To bring down a real network interface, use the following command as root, replacing N with the
number corresponding to the interface (eth0 and eth1).
/sbin/ifdown ethN
Checking the Status of Network Int erfaces
If you need to check which network interfaces are up at any given time, type the following:
/sbin/ifconfig
To view the routing table for a machine, issue the following command:
/sbin/route
3.4. Multi-port Services and LVS
LVS routers under any topology require extra configuration when creating multi-port LVS services. Multi-
port services can be created artificially by using firewall marks to bundle together different, but related
protocols, such as HT T P (port 80) and HTTPS (port 443), or when LVS is used with true multi-port
protocols, such as FTP. In either case, the LVS router uses firewall marks to recognize that packets
destined for different ports, but bearing the same firewall mark, should be handled identically. Also, when
combined with persistence, firewall marks ensure connections from the client machine are routed to the
same host, as long as the connections occur within the length of time specified by the persistence
parameter. For more on assigning persistence to a virtual server, see Section 4.6.1, “T he VIRTUAL
SERVER Subsection”.
Unfortunately, the mechanism used to balance the loads on the real servers — IPVS — can recognize
the firewall marks assigned to a packet, but cannot itself assign firewall marks. T he job of assigning
firewall marks must be performed by the network packet filter, iptables, outside of Piranha
Configurat ion Tool.
3.4.1. Assigning Firewall Marks
To assign firewall marks to a packet destined for a particular port, the administrator must use
iptables.
This section illustrates how to bundle HT T P and HT T PS as an example; however, FT P is another
commonly clustered multi-port protocol. If an LVS is used for FTP services, refer to Section 3.5,
“Configuring FTP” for configuration details.
The basic rule to remember when using firewall marks is that for every protocol using a firewall mark in
Piranha Configuration Tool there must be a commensurate iptables rule to assign marks to the
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