Specifications

Match Functions
Equalizer Installation and Administration Guide 133
Table 61: non-URI Match Functions
non-URI Match Function Description
any()
This
function always evaluates to true.
client_ip(string)
This
function evaluates to true only if the IP address of the client
machine making the connection matches the string argument.
The string can be a simple IP address (e.g., “192.168.1.110”), or
an IP address in Classless Inter-Domain Routing (CIDR)
notation (e.g., “192.168.1.0/24”). This function can be useful in
restricting match expressions to a particular client or group of
clients, which can aid in debugging a new match rule when a
cluster is in production. Only the specified clients match the rule,
leaving other clients to be handled by other match rules.
debug_message(string)
This
function always evaluates to true. It writes the string
argument
to the Event Log for the cluster (View > Event Log).
This function can be logically ANDed and ORed with other
functions to write debug messages. Use this function for testing
and debugging only. Do not use it in production environments,
since it has a negative impact on performance.
ignore_case() This function always evaluates to true, and is intended to be used
to apply the ignore_case flag for comparisons when it is not set
on the cluster. When this function is ANDed with other functions,
it has the effect of forcing case to be ignored for any comparisons
done by the match rule.
observe_case() This function always evaluates to true, and is intended to be used
to override the ignore_case flag for comparisons when it is set
on a cluster. When this function is ANDed with other functions, it
has the effect of forcing case to be honored for any comparisons
done by the match rule.
http_09() This function takes no arguments and evaluates to true if the
HTTP protocol used by the request appears to be HTTP 0.9. This
is done by inference: if an explicit protocol level is absent after the
request URI, then the request is considered HTTP 0.9.
method(string) This function evaluates to true if the string argument exactly
matches the Request Method (e.g., GET, POST, etc.) specified
in the request. Note that by default Equalizer forwards packets to
servers without determining whether or not the method specified
in the request is valid (i.e., is a method specified in Section 9 of
RFC2616). One use of the method() function is to be able to
override this default behavior and prevent invalid requests from
being forwarded to a server.
[header match functions] [No exact match header() function is supplied. See “Match
Function Notes” on page 136, for the supported values for
header.]
header_prefix(header, string) This function evaluates to true if the selected header is present
and if the string-valued argument string is a prefix of the
associated header text.
header_suffix(header, string) This function evaluates to true if the selected header is present
and if the argument string is a suffix of the associated header text.