Cachemov and Uptime

In this column, I want to tell you about two tools I found in the Microsoft Windows 2000 Server Resource Kit Supplement One. Cachemov works with Win2K's helpful Offline Files feature. Offline Files lets you cache network files on your local hard disk. When you want to work with a cached network file, Offline Files quickly checks whether the server's copy of the file has changed. If it hasn't, your system delivers the file from the local cache, which is far faster than retrieving the file from the network. (For more information about Offline Files, see Todd Logan, "The Ins and Outs of Offline Files," page 69, and "Related Articles in Previous Issues.")

I locally cache all the files that I frequently use. But those files are numerous and contain a lot of data, and Offline Files keeps all of it on the same hard disk that contains the OS. On my system, that hard disk is fairly full, so I added a hard disk to hold the cached files and called the new hard disk drive D.

But how did I tell Offline Files to cache my files on the new drive? I simply typed Cachemov at a command line, and a prompt asked me what drive I wanted Offline Files to use. I could have typed

cachemov -unattend d:\

to use the command in unattended mode.

Now, my data is on a physically secure server, which I regularly back up, and my server's battery backup protects the data. But I also have local copies of the data—just in case the server is temporarily unavailable—and plenty of space for those copies.

Uptime is a Win2K Professional command-line tool that reads a local or remote server's System event log and produces reports about the system's uptime. Type Uptime on a command line to get a report about the local machine, or type a machine name after the command to produce a report about a remote server. A summary like the one that Figure 1 shows will tell you exactly how long your system has been up.

If you append the /v and /s switches to the command, you'll get a verbose listing of every instance in which the server has gone down, been booted up, or suffered a blue screen. You'll also get an availability percentage, so you can wave a five-nines (99.999 percent) availability report at your boss if your system has been up long enough.

Uptime interrogates the System log and extracts the shutdown, startup, and blue screen messages (if you haven't disabled the blue screen messages in Control Panel). Uptime uses the machine's heartbeat to return the statistics. Introduced in Windows NT 4.0 Service Pack 4 (SP4), the heartbeat is a last-alive timestamp that Windows writes to the registry at 5-minute intervals. The OS uses the heartbeat in conjunction with the dirty shutdown event (System log event ID 6008) to estimate how long the system has been down. Although Uptime's ability to report availability statistics depends on the heartbeat, you can still use Uptime to interrogate servers whose heartbeat is disabled about how long they've been up.

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