Extreme Networks EPICenter 5.0, Manual, Page: 66 / 208

66 EPICenter Concepts and Solutions Guide
Managing your Network Assets
• You can restrict the discovery to devices running SNMPv1 (the default) or allow it to discover
devices running SNMPv3 as well.
You can also control the range of IP addresses over which EPICenter will try to discover the devices it
can manage:
• You can specify a single address or subnet specification, using wildcard characters as needed
• You can specify the start and end addresses of a range of IP addresses
• You can also use a subnet mask to modify the range of addresses to be searched.
Valid wildcard characters are * , ? , and - (dash):
*
acts as a wildcard for the entire octet (0-255).
? is a wildcard for a single digit (0-9).
- lets you specify a range for any octet. You can use this in more than one octet. Note that you
cannot combine the dash with another wildcard in the same octet. The following are some examples
of using wildcard characters in an IP address
The subnet mask can also be used to specify a subnet not on the octet boundary: for example, specifying
an IP address of 10.203.16.0 with a mask of 22 will expand to the range 10.203.16.1 - 10.203.19.254, a
range of 1022 addresses.
The ranges specified through the use of wild cards and the subnet mask interact in that the two
specifications are combined with an “and” conjunction. This means that the more restrictive of the
specifications will be the one to take effect.
IP addresses are processed prior to starting the discovery, and IP addresses that contain 255’s in the host
portion are eliminated. This is based on the IP address as well as the subnet mask.
The EPICenter Discovery dialog lets you create a Discovery request that combines multiple discovery
specifications. This means that within a single discovery operation you can have EPICenter discover
devices in different address ranges, or search using several different read community strings, for
example.
Figure 28 shows an example of a set of device discovery criteria that will all be used during a single
discovery operation.
10.203.0.* polls 10.203.0.0 through 10.203.0.255
10.203.?.?? polls 10.203.0.0 through 10.203.9.99
10.203.0.1? or 10.203.0.10-19 both specify the same range: 10.203.0.10 through 10.203.0.19
10.203.0-2.10-30 polls
10.203.0.10 through 10.203.0.30
10.203.1.10 through 10.203.1.30
10.203.2.10 through 10.203.2.30