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The NTP protocol permits the use of crypto to authenticate clients and servers to each other, as well as between time servers. By default, SLES10 is set up to allow the v3 method of using symmetric keys, but not the v4 method that uses public/private keys. If you want to use the v4 method, this is the tip for you.

Background

By default SLES runs NTP inside a chroot jail. This can be changed from the YaST NTP config screen if you wish. This is a more secure method of running NTP. The chroot jail's root is at /var/lib/ntp/.

Additionally, ntp runs with an AppArmor profile loaded against it for added security.

Getting NTPv4 auth to work

There are 4 steps to get this to work.

  1. Copy the .rnd file to the chroot jail
  2. Run ntp-keygen
  3. Modify the AppArmor profile for /usr/sbin/ntpd to allow read access to the new files
  4. Modify the /etc/ntp.conf file to enable v4 auth.

Copy the .rnd file to the chroot jail

By default, there should be a .rnt file at /root/.rnd. If so, copy this to /var/lib/ntp/etc/.rnd. If there is no file there, one can be generated through use of openssl.

timehost:~ # openssl rand -out /var/lib/ntp/etc/.rnd 1

Run ntp-keygen

Change-directory to /var/lib/ntp/etc, and execute the following command:

timehost:~ # ntp-keygen -T

This will drop a pair of files in the directory you run it, so running it while in /var/lib/ntp/etc saves you the step of copying them to this directory.

Modify the AppArmor profile

This is done through YaST

  1. Launch YaST
  2. Go to the "Novell AppArmor" section, and enter the "Edit Profile" tool.
  3. Select "/usr/sbin/ntpd" and click Next.
  4. Click the "Add Entry" button and select File.
  5. Browse to /var/lib/ntp/etc/.rnd and click the "Read" permissions check-box, and click OK
  6. Repeat the previous two steps to add the two files created by ntp-keygen, named "ntpkey_cert_[hostname]" and "ntpkey_host_[hostname]".
    1. Note: AppArmor behavior changes between SP1 and SP2. In SP1 you can use the link files, in SP2 you need to specify the link targets.
  7. Click Done on the main Profile Dialog
  8. Agree to reload the AppArmor profile

Modify /etc/ntp.conf

The YaST tool for NTP doesn't allow for v4 configurations, so this has to be done on the command line. Open the /etc/ntp.conf file with your editor of choice, and insert the following lines before your "server" lines:

keysdir /var/lib/ntp/etc/
crypto randfile /var/lib/ntp/etc/.rnd

Then append the word "autokey" to the server and peer lines of your choice. At this point, you should be able to restart ntpd, and it will use authentication. This is a very basic NTPv4 configuration setup, but this should set the ground up for more complex configs.

If you've been getting core files generated by ndsd on your Linux servers, and want to call Novell Support about it, there are a few things you can do to maximize what Novell will get out of the files themselves. You may not get much, but these will help the people with the debug symbols figure out what's going on.

Packaging the Core


First and foremost, you already have the tool to package core files for delivery to Novell already on your system. TID3078409 describes the details of how to use 'novell-getcore.sh'. It is included on 8.7.3.x installations as well as 8.8.x installations.

Running it looks like this:
edirsrv1:~ # novell-getcore -b /var/opt/novell/eDirectory/data/dib/core.31448 /opt/novell/eDirectory/sbin/ndsd
Novell GetCore Utility 1.1.34 [Linux]
Copyright (C) 2007 Novell, Inc. All rights reserved.


[*] User specified binary that generated core: /opt/novell/eDirectory/sbin/ndsd
[*] Processing '/var/opt/novell/eDirectory/data/dib/core.31448' with GDB...
[*] PreProcessing GDB output...
[*] Parsing GDB output...
[*] Core file /var/opt/novell/eDirectory/data/dib/core.31448 is a valid Linux core
[*] Core generated by: /opt/novell/eDirectory/sbin/ndsd
[*] Obtaining names of shared libraries listed in core...
[*] Counting number of shared libraries listed in core...
[*] Total number of shared libraries listed in core: 72
[*] Corefile bundle: core_20080725_092227_linux_ndsd_edirsrv1
[*] Generating GDBINIT commands to open core remotely...
[*] Generating ./opencore.sh...
[*] Gathering package info...
[*] Creating core_20080725_092227_linux_ndsd_edirsrv1.tar...
[*] GZipping ./core_20080725_092227_linux_ndsd_edirsrv1.tar...
[*] Done. Corefile bundle is ./core_20080725_092227_linux_ndsd_edirsrv1.tar.gz


Once you have the packaged core, you can upload it to ftp.novell.com/incoming as part of your service-request.

Including More Data


If you're lucky enough to be able to cause the core file to drop on demand, or it just plain happens often enough that repetition isn't a problem, there is one more thing you can do to include better data in the core you ship to Novell. TID3113982 describes a setting you can add to the ndsd launch script (/etc/init.d/ndsd) that'll include more data. The TID describes what is being done pretty well. In essence, you're using an alternate malloc call that fails with better information than the normal one. You don't want to run with this set for very long, especially in busy environments, as it impacts performance. But if you have a repeatable core, the information it can provide is better than a 'naked' core. Setting MALLOC_CHECK_=2 is my recommendation.

Be sure to unset this once you're done troubleshooting. As I said, it can impact performance of your eDirectory server.

A good article on trustees

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Over on the Novell Cool Solutions site, Marcel Cox just posted an article about how Trustees are handled on the Novell Filesystems (TFS and NFS). If you wanted to know the fundamentals of how ACLs are done on NSS volumes and how it relates to eDirectory, this is a good start.

Novell news

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Two Cool Blogs posts in the past few days have held some nice tidbits.

Jason Williams says that the Novell Client for Vista is due out mid August
, so long as a key defect registered with Microsoft gets fixed.

Jaimon Jose says that eDir 8.8 SP2 is also due out real soon. SP2 apparently involves some serious performance enhancements.

Both of these are technologies associated with the elusive OES2. We need the Client for Vista as soon as they can get it to us, so I'm not surprised they're considering releasing that independently of OES2. SP2 for eDir 8.8 is one thing I figure will be included in OES2 by default. As that's an independent product as well, having it release independently is nice. This means that two technologies that could be blockers for OES2 are finally being kicked into the real world.

In news unrelated to WWU at all, Bonsai, the next GroupWise version, seems to be getting closer to deployment. They're nearing 'code complete' and will soon start the Authorized Beta phase.

OES2 and AFP

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If you're an instituion of education like us, chances are real good you have PowerBooks and other Mac hardware desiring access to your NetWare/OES servers. It turns out I missed something while at BrainShare. OES2-Linux does NOT have an eDir integrated AFP stack like NetWare does. Whoa.

Details here: http://www.novell.com/coolblogs/?p=836

That's Jason Williams posting, and he is the Project Manager to OES. I spoke with him for a while during Meet the Experts regarding the concurrency concerns we have with OES in general. He has been on Novell Open Audio several times, so I know his voice. He was run downright ragged during BrainShare, which is very not surprising due to his level of oversight of a major product.

He's asking for people who need AFP to talk to them about it. The details of what he's looking for is in the posting I linked above. I've sent in my own impressions, and I've forwareded it to internal people who are Very Concerned about how Mac interacts with our NetWare servers.
I just got a mail from the company that manages CoolSolutions. They're changing how they handle the points you earn for submitting articles, tips, and tools. Quote:
Beginning December 31, 2006, points will expire after one year of account inactivity. Point balances of members who have had no activity within the last calendar year (2006) will expire on Dec. 31, 2006.

Points will not expire as long as you participate in one of the following activities at least once a year:

- Earn points by participating in any of the opportunities listed at Novell Rewards
- Redeem points by requesting an award at http://www.novell.com/company/rewards

If you have any questions, please feel free to e-mail us at rewards@webwiseone.com
So. Looks like they're trying to clean up a bit. People who haven't submitted anything recently but are high contributers will get edged out. There are a few in the top 20. Me? My last submission was an AppNote in August, so I'm in good shape.

One more AppNote, and I can get that 80GB iPod. Mmmm. Or maybe those Bose QuietComfort 3 headphones.

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