Coyote Point Systems E350GX, Installation And Administration Manual

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Managing Servers
Equalizer Installation and Administration Guide 145
3. If you made any changes to the default configuration values, click the
commit
button to save your changes.
Configuring Outbound NAT
The
enable outbound NAT
global parameter allows servers on a non-routable network to communicate with hosts
on the Internet by mapping the server’s IP address to another IP address that is routable on the Internet. It is disabled
by default. Enabling outbound NAT has a performance impact since Equalizer needs to modify every server
response. This parameter should only be enabled when the system is configured in dual network mode, and is
incompatible with single network mode operation.
max connections
Sets the maximum number of permitted open connections for the
server. Once this limit is reached, no more traffic is routed to the server
until the number of open connections falls below this limit. This limit is
set by default to 0, which means that there is no maximum connections
imit on the server. See “Setting Maximum Connections per Server” on
page 148 for more information.
initial weight
An number between 0 and 200 that indicates a server’s processing
power relative to the other servers in the cluster. The default is 100. A
value of 0 disables the server (no traffic will be routed to the server).
For information about selecting an appropriate initial weight, refer to
“Adjusting a Server’s Initial Weight” on page 147.
hot spare
Enable the
hot spare
check box if you plan to use this server as a backup
server, in case the other servers in the cluster fail. Checking
hot spare
forces Equalizer to direct incoming connections to this server only if all
the other servers in the cluster are down. You should only configure one
server in a cluster as a hot spare.
For example, you might configure a server as a hot spare if you are
using licensed software on your servers and the license allows you to
run the software only on one node at a time. In this situation, you could
configure the software on two servers in the cluster and then configure
one of those servers as a hot spare. Equalizer will use the second server
only if the first goes down, enabling you to make your application
available without violating the licensing terms or having to buy two
software licenses.
quiesce
When enabled, Equalizer avoids sending new requests to the server.
This is usually used in preparation for shutting down an HTTP or HTTPS
server, and is sometimes also called “server draining”. Please see
“Shutting Down a Server Gracefully” on page 149.
Note : if a cluster
receives a new client request when all non-quiesced servers (including
hot spares) are unavailable, then the request will be load balanced
across all the quiesced servers in the cluster.
dont probe
D
isables High Level Probes (TCP and ACV) for the server. This is usually
used to disable probe checks for a particular server without changing
the probe settings for the entire cluster.
dont persist
Disables persistence for the server when the
persist
flag (Layer 7
cluster) or a non-zero
sticky time
(Layer 4 cluster) is set on the cluster.
For a Layer 7 cluster, this means that no cookie will be inserted into the
response header on the way back to the client. For a Layer 4 cluster, no
sticky record is set. This flag is usually used to disable persistence for a
hot spare. For an example, see “Maximum Connections Limits,
Responders, and Hot Spares” on page 149.