Enterprise Software

Safely remove a NetWare server from your NDS tree

In a perfect world, servers would never crash. In reality, servers crash or get old and must be replaced. John Sheesley shows you the two methods for removing servers from your NDS tree.

As much as you might hope that you’d purchase a server that would last forever, eventually the time will come when you have to replace it, either because the server crashes or because you’ve bought a new one. Unfortunately, you can’t just go into NetWare Administrator, delete the server object from the NDS tree, and go about your business. I’ll show you what you need to do to remove a server from your NDS tree without damaging the tree in the process.

A tale of two servers
There are two basic reasons you’d have to remove a server from your NDS tree—either the server has crashed and you won’t be bringing it back up or you’re retiring it from service. As far as your NDS tree is concerned, both are equally bad: In both situations a server exists that it can’t communicate with. From an administrator’s point of view, you have to know two procedures for repairing the tree. As always, before you attempt to do anything this radical with your NDS tree, make sure you have complete backups of all of your servers as well as your NDS.

Retiring a server from production
If you’re lucky, you don’t have to deal with hardware failures or system crashes. You can just run your NetWare server until it’s so outdated you can replace it with a new server. For a network administrator, this scenario is the simplest one when it comes to removing a server from the NDS tree. This scenario is best because you still have the original server. By using the server’s own Install program, you can have the server take itself out of the tree. In the process, the server removes all replicas and moves any information it contains to other servers in your NDS tree. This process ensures that you don’t lose any information at all and your entire NDS tree stays intact.

The first thing you must do before removing a server from your NDS tree is to make sure that you’ve moved all of your data off the NetWare server you’re retiring. (Note that once you’ve removed NDS from the server, you’ll have to reinstall it if you need to get data off of the server.) After that, you should ensure that NDS is running properly and that there are no synchronization issues with your server. To do so, you can use the NDS Manager.

Start NDS Manager from your administration workstation by going to the SYS:\Public\Win32 directory and running NDSMGR32.EXE. When NDS Manager starts, select the container object where your NetWare server resides from the left pane. You’ll see your NetWare servers appear in the Server pane on the right. Select the server you’re going to retire, right-click it, and click Information. You’ll see the Replica Information screen shown in Figure A.

Figure A
Use NDS Manager to check for errors before retiring a server.


Check the Current Sync Error field. If all is well with your server, the value for this field should be No Error and you may proceed with the retirement. Just close down NDS Manager and go on.

If you see an error code in the field, you must resolve this error before you can go any further. You can find out more information about the error by clicking the question mark (?) button next to the Current Sync Error field. You can check NDS and resolve errors by following the instructions in the Daily Drill Down “Checking the health of NDS.”

After you’ve made sure that there are no synchronization issues to be concerned about, check to see if your server contains the Master replica or a Read/Write replica for your NDS tree. If your server contains a Read/Write replica, you don’t have anything to worry about. If the server contains the Master Replica, you must first move the Master replica to another server before proceeding.

To do so, select the server you want to contain the Master replica in NDS Manager. Right-click the server in the right pane and select Change Type. When the Change Replica Type window appears, select Master in the Replica box and click OK. NDS Manager will quickly check to make sure that it can successfully change the replica type on the server. If it can, it will display another Change Replica Type window that says that all preconditions have been met. Click OK to make the change. When NDS Manager reappears, you’ll see that your server is now the master, and that the server you want to retire now contains only a Read/Write replica.

Next, you must make sure that the server you want to retire isn’t configured to be a Single or Reference Time Server. If it is, you must make another server the Single or Reference Time Server for your NDS tree. You can check the server’s Time status by going into Monitor at your server’s console prompt and checking the server’s Time configuration.

Start Monitor by typing load monitor at the server console and pressing [Enter]. When you see the Available Options menu appear, highlight Server Parameters and press [Enter]. Next, select Time from the Select A Parameter Category menu. Scroll through the Time Parameters screen until you see the Default Time Server Type field. If the field is set to Single or Reference, edit it and change it to Secondary. You’ll then need to go to another server and change that server to be the Single or Reference Time Server for your NDS tree.

After you’ve made sure that NDS is working properly, you can remove NDS from the targeted server. You’ll do so using NWConfig. Go to the server you want to retire. From the server’s console prompt, type load nwconfig and press [Enter]. When the Configuration Options menu appears, highlight Directory Options and press [Enter]. You’ll see the Directory Services Options menu appear, as shown in Figure B.

Figure B
You can remove NDS from the server using NWConfig.


Highlight Remove Directory Services From This Server and press [Enter]. NWConfig will display a very large purple screen warning you about the implications of removing NDS from your server. When you press [Enter] to get past this warning screen, you’ll see the Remove Directory Services menu.

If you’re not absolutely sure you want to remove NDS, press [Esc] or highlight No and press [Enter] to stop NWConfig from continuing. Otherwise, highlight Yes and press [Enter] to remove NDS.

NWConfig will immediately prompt you to enter the user ID and password for your Admin account. Enter the information in the appropriate fields and press [Enter]. After you successfully log in to your NDS tree, NWConfig will display a message concerning external references.

External references are properties of NDS objects that point to the NDS server object you’re about to remove. If you have a Print Queue object associated with your server, NWConfig will change the name of the Print Queue object and remove the reference. Press [Enter] to have the external references changed.

NWConfig will then display the Placeholder Object Distinguished Name menu. At the prompt, you’ll see the fully distinguished NDS name for your server. Press [Enter] to continue. NWConfig will prompt you to enter the level from which it should start removing references. By default, NWConfig will choose [Root]. Unless you have a good reason for selecting a lower level, just press [Enter] to continue.

NWConfig will search for and remove references to the server. After dealing with all of the external references, NWConfig will remove NDS from your server. Go back to your administration workstation and double-check NDS Manager. Your retired server will no longer exist in the NDS tree. You can then go into NetWare Administrator or ConsoleOne and delete or modify any remaining objects that point to the retired server.

Removing a crashed server from the tree
If a server has crashed in your NDS tree and you don’t intend to replace it, you have a few more hoops to jump through to remove it from your NDS tree. Removing a crashed server becomes more problematic because a crashed server can cause time synchronization and replication issues that you must deal with before trimming the NDS objects from your tree.

Start by verifying that time is completely synchronized on your network. To do so, go to one of your remaining NetWare servers, type load dsrepair from the console prompt, and press [Enter]. When the available options menu appears, select Time Synchronization and press [Enter]. DSRepair will generate a report on time synchronization for all of the servers in your tree. Naturally, the crashed server will appear to have an error. So long as the other servers are synchronized, you’re in good shape. If they aren’t, you should resolve the time synchronization errors before proceeding. You may have to set one of the servers to be the Single or Reference Time Server for your network and allow time to synchronize.

Once time is synchronized across your network, you must check to see if the crashed server contained the Master or Read/Write replica for your NDS tree. You can do so by using NDS Manager as described above. If the crashed server only contained a Read/Write replica, you don’t need to worry much, but if the crashed server contained the Master replica, you must do some additional work.

First, you must select a server to contain the new Master replica. The best choice is the fastest server on your network with the best network connection and the least work to do in terms of sharing files and print queues. Load DSRepair from that server’s console.

From the Available Options menu, select Advanced Options. When the Advanced Options menu appears, select Replica And Partition Operations. You’ll then see the replicas stored on this server. Select the replica and press [Enter].

From the Replica Options, Partition menu, select Designate This Server As The New Master Replica and press [Enter]. DSRepair will then assign the server you’re on to be the new master and replicate the changes to other NetWare servers in your tree.

After you’ve set a new Master replica, you must clean up your NDS tree. Start by running NDS Manager and removing the crashed server. To do so, start NDS Manager and press [Ctrl]F to display your servers and the NDS tree at the same time. Right-click the server you want to delete in the Server pane of NDS Manager and select Delete. When the Delete Server window appears, click Yes. NDS Manager will check for any dependencies and double-check to make sure you want to delete the server. Click Yes. NDS Manager will then remove the server from the replica and any server in the replica ring as well.

Next, start NetWare Administrator. Look through the NDS tree for objects associated with your crashed server. You may have to remove volume objects and print queues associated with the server. Make sure you reconfigure any logon scripts for your users to point to new volumes and queues you want the users to access instead of the old ones. You’ll be able to quickly find the orphaned objects in the tree because their icons will contain a yellow question mark (?).

Finally, check DSRepair again to make sure that synchronization is working properly. Load DSRepair on your new Master replica server. Select Advanced Options | Replica And Partition Operations | current replica | View Replica Ring. If the crashed server still exists in the replica ring, select it and press [Enter]. When you see the Replica Options: Server screen, select Remove This Server From The Replica Ring.

Carry on
After you’ve removed the server and any associated objects from the NDS tree, your users shouldn’t notice any problems at all. You may have to reset home directories and print queue configurations, but overall, your tree should remain unaffected.
1 comments
alex2mil
alex2mil

I have the case of obsolete equipment, 10q