Limits

Overview

EZproxy has a variety of limits that can be changed to meet the needs of your institution. Each limit is named MaxSomething where Something describes the specific limit involved.

The following provides the name of each limit, its two-letter abbreviated form, its default value, and its purpose.

In normal use, MaxLifetime should appear before the first Title line in config.txt/ezproxy.cfg. All other settings may appear anywhere in config.txt/ezproxy.cfg, although it is more typical to include them all at the top. They should appear in config.txt/ezproxy.cfg as their name followed by their new value, such as:

MaxVirtualHosts 300

Settings

MaxConcurrentTransfers (MC, default 200) determines how many HTTP transfers can be in progress concurrently. Most web browsers are configured to attempt four simultaneous HTTP transfers so that they can load web pages and graphics at the same time. The default value of 200 allows for 50 people to concurrently downloading 4 files each without reaching this limit.

MaxLifetime (ML, default 120) determines how long in minutes an EZproxy session should remain valid after the last time it is accessed. The default of 120 determines that a session remains valid until 2 hours after the last time the user accesses a database through EZproxy. MaxLifetime is the only setting that is position dependent in config.txt/ezproxy.cfg. In normal use, it should appear before the first TITLE line.

MaxSessions (MS, default 500) determines the maximum number of EZproxy sessions that can exists concurrently. A user's session is created during login and ends after MaxLifetime minutes of inactivity (default 2 hours) have occurred or when the user accesses a URL like http://ezproxy.yourlib.org:2048/logout to explicitly logout.

MaxVirtualHosts (MV, default 200) determines the maximum number of virtual web servers that EZproxy can create. A virtual web server represents a single host name/port combination. For example, if EZproxy assigns port 2050 to www.somedb.com, 2051 to www.somedb.com:180, and 2052 to www.otherdb.com, these three ports represent three virtual hosts. In normal use, increase this parameter by no more than 50 - 100 each time, as it provides a safe guard against configuration errors in config.txt/ezproxy.cfg that might lead to the creation of excessive, unneeded virtual hosts.