🚀 go-pugleaf

Tim Reed writes
> 
> We have 4 NeXTs (soon to be 5) and 2 Suns on our network. I was  
> wondering if cloning the netinfo manager for the NeXTs is advisable 
>
YES YES YES

> or just a waste of time.
> 
NO NO NO

> Does everyone who manages a network use NI clones?
>
They should.

> Have there been any problems because of the clones?
>
Not for me. Clones keep a read-only copy of the master,
so unless you are muching around with files, it is difficult
to screw them up.

> Has it saved the day for anyone?
> 
Yes. In addition to caching, you have an up-to-date backup
of your most critical (in our case) network information.

Later,

John
-- 
John Robison - Oceania Health Care Systems 
john@oceania.com - NeXTMail Gladly Accepted

In article <1992Aug6.153031.14574@newsgate.sps.mot.com>  
reed@prism.sps.mot.com (Tim Reed) writes:
> 
> We have 4 NeXTs (soon to be 5) and 2 Suns on our network. I was  
> wondering if cloning the netinfo manager for the NeXTs is advisable  
> or just a waste of time.
> 
> Does everyone who manages a network use NI clones?
> Have there been any problems because of the clones?
> Has it saved the day for anyone?
Here are the reasons I can come up with for having clones:
If your master server goes down, any machines which happen to be booting  
can attach to the clone and work happily until the master comes back up,  
at which time the master and clone will get back into sync.

If you have a whole slew of machines in several subnets (like we do at  
UIUC), if your top-level master is in subnet A and you have a network  
netinfo server in subnet B, it is smart to make that network netinfo  
server in subnet B a clone of that master top level domain.  When machines  
in subnet B attach to a top level machine, they will likely connect with  
the machine in their own subnet because broadcast traffic is much faster  
than going across 3 routers to the other subnet.

If your master server's netinfo (/etc/netinfo/masterlevel.nidb) directory  
gets frazzled, it is possible to reconstruct it from your clone's.  I have  
never succeeded in this (it's always been easier to go from the last  
backup), but the general steps should be:
- use niutil -createprop -t clone/toplevel master clone.machine.edu
- follow the directions for 'making a clone' on the old master server  
(that means nidomain -c to clone what is now the master server)
- Change the master property back in the top level if you want to make the  
original master the master once more
- reboot !!!
--
David Lemson                                           (312) 732-4741
FNBC Sys Admin (Summer) UIUC NeXT Campus Consultant(rest of the time)
E-mail to: lemson@fnbc.com                          NeXTMail accepted

In article <1992Aug6.153031.14574@newsgate.sps.mot.com>  
reed@prism.sps.mot.com (Tim Reed) writes:
> 
> We have 4 NeXTs (soon to be 5) and 2 Suns on our network. I was  
> wondering if cloning the netinfo manager for the NeXTs is advisable  
> or just a waste of time.

Ask yourself:  What will happen to my network if my master NetInfo machine  
crashes?  Assuming you have backed it up, a clone allows your network to  
operate while you are building a new master.  Also, a clone gives the  
network some efficiency.  If the NetInfo master is heavily loaded then the  
other machines must wait on the master for a NetInfo request. 

> Does everyone who manages a network use NI clones?

Any network I manage of more than two machines has a clone.  Otherwise I  
rely on backups.

> Have there been any problems because of the clones?
> Has it saved the day for anyone?

Yes.  Clones and Master can get confused and confuse each other.  This  
occurs, however, when things are confusing. Don't despair, this can happen  
when there isn't a clone too.  Confusing things are known to happen when:
*	There is more than one master,
*	The serves properties are screwed up,
*	A server gets confused (for example: unpredictable things that  
occur when a disk becomes 100% full).

Overall I like NetInfo but I do take precautions.  I back up my system  
regularly and I have a script that runs every eight hours that backs up  
the NetInfo databases to a well known (local) directory on the master.  I  
recycle the back ups after a week (another script function).

--
Dennis P. Glatting
Sr. Technical Manager
Trirex Systems Inc.
315 Post Road West
Westport, Connecticut   06880
203-221-4614