How to configure interim intervals on Windows 2000 Server

What is interim intervals

The interim intervals allows writing records in to IAS log file with specified periodicity. In the usual mode each connect consist of the 2-4 records in the IAS log file:

  • Access request
  • Access accept
  • Accounting request start
  • Accounting request stop

i.e. by that records you can see statistics while connect was finished only. With interim intervals each XX seconds statistic for active connects will be written. You may see active connects duration, transmit bytes nearly real-time. Why nearly? Because standard RRAS server in Windows 2000 not allows to define interim interval less then 60 seconds. May be this is possible in other Microsoft IAS server clients.

How to setup interim intervals

At first step Acc-Interim-Interval attribute must be added:

  • Run the IAS management console
  • Select needed remote access policy
  • Open properties of that policy
  • Click on Edit Profile… button
  • Select advanced tab
  • Add attribute Acct-Interim-Interval with 60 value for sample.
    Value=60 is an interval in the seconds. This is interval between records for active connects that’s will be added in to IAS log file.
  • Save changes by click Apply or OK

Now we must say for IAS server that interim records must be saved in to IAS log file:

  • Run the IAS management console
  • Select Remote Access Logging
  • Open properties of Local File by right click
  • Set check Log Periodic Status
  • Save changes

That’s all. Now all new connects with duration more then 60 seconds will have additional interim records in the IAS log file.

How to see that interim intervals was work

  • Run IAS Log Viewer and open active log file.
  • Set filter Connect Result = ‘Online’. Now you see active connects at the current time only. Each XX seconds you must see that an input octets/output octets for active connects will be changed. This test shows that interim records rightly interpreted by IAS Log Viewer.
  • Open records view and show column “Acct-Status-Type”. Each XX seconds you must see that new records will be added. Those records contain “Interim Update” value in the “Acct-Status-Type” column. There are interim records. Its automatically parsed by IAS Log Viewer and you may see statistic of the active connects in the connects view.

What positive in the interims

Activity of the current users you may see nearly in real-time. You may detect load of the IAS server approximately.

What negative in the interims

One negative thing only. Ias log file grow more quickly. Each interim records take 200-300 bytes. IAS Log file grow very fast if you have many long online connects. May be this is important remark for off interim records.