Cabletron Systems 2000 User Manual

Also see for 2000: User guide Getting started guide

Contents

Advanced Alarm Configuration3-19Alarm Configuration6. In the Alarm Interval field, enter the amount of time over which the selectedvariable will be sampled. At the end of the interval, the sample value will becompared to both the rising and falling thresholds. There is no practical limit tothe size of the interval (as the maximum value is 24,855 days 3 hours 14minutes and 7 seconds — over 68 years!); the default value is 1 minute.NOTEIf you wish to set an alarm on an object whose instance is non-integral — for example, aHost Table object indexed by MAC address — or on an object with multiple indices, like aMatrix Table entry (which is indexed by a pair of MAC addresses), you must followcertain special procedures for defining the instance. For these OIDs, the instancedefinition must take the following format:table index.length(in bytes).instance(in decimal format)For the first byte of the instance, you must use the index number of the table whichcontains the OID you want to track. For example, to set an alarm on an object in the HostTable, define the first byte of the instance as the index number assigned to the specific HostTable you want to check. These index numbers are assigned automatically as the tableentries are created; no two tables — even if they are on different interfaces — will sharethe same table index number.Second, you must specify the length, in bytes, of the index you will be using. Again, in thecase of an object in the Host Table, that value would be 6, since Host Table entries areindexed by MAC address — a six-byte value.Finally, you must specify the index itself, in decimal format. In the case of a MACaddress, that means you must convert the standard hexadecimal format to decimal format.To do this, simply multiply the first digit of the two-digit hex number by 16, then add thevalue of the second digit. (For hex values represented by alphabetical characters,remember that a=10, b=11, c=12, d=13, e=14, and f=15.) A hex value of b7, for instance,is represented in decimal format as 16 x 11 + 7, or 183.So, for example, the instance for an object in the Hosts group might read as follows:2.6.0.0.29.170.35.201where 2=the host table index; 6=the length in bytes of the index to follow; and0.0.29.170.35.201=the decimal format for MAC address 00-00-1d-aa-23-c9.For objects with multiple indices — such as objects in a matrix table — you must addadditional length and index information to the instance definition, as illustrated below:3.6.0.0.29.170.35.201.6.0.0.29.10.20.183where 3=the matrix table index; 6=the length in bytes of the index to follow;0.0.29.170.35.201=the decimal format for MAC address 00-00-1d-aa-23-c9; 6=the lengthin bytes of the next index; and 0.0.29.10.20.183=the decimal format for MAC address00-00-1d-0a-14-b7.Additional instance issues may exist for FDDI objects; if you’re unsure how to assign aninstance, use the MIBTree utility to query the object of interest, and note the appropriateinstancing on the returned values.