network transition occurred in DirectoryService.server.log

[drixselecta]

Hi guys, first post on this forum as I am quite new to Mac OS X admin.

We run a very handsome XServe G5 with Mac OS X Server 10.4.3 as Gateway (DNS, DHCP, NAT, ipfw, VPN), OD Master, Windows Standalone, file and print server.

Everything seems fine, but I get this message:

“network transition occurred”

…every 30 seconds in my DirectoryService.server.log…

I have looked for other posts about this one but found no convincing answers. Could someone at least tell me where it comes from so that I can try to fix it?

[drixselecta]

And I tought that it was a simple question… So I can’t keep the server up for more than 4 days. Eventually it says network transition – , which I can only see after I reboot, because at that point, nothing can login into the server: monitor, admin, WGM, gateway setup assistant, ssh and afp.
In verbose mode and with my kerberos ticket in the pocket (which I can still get), the ssh identification stops by:

debug1: identity file /Users/cedric/.ssh/identity type -1
debug1: identity file /Users/cedric/.ssh/id_rsa type -1
debug1: identity file /Users/cedric/.ssh/id_dsa type -1

If I do a hard reboot, everything goes back to normal…
Any ideas? Is anyone experiencing the same?

Please help me!

[drixselecta]

Is that what could trigger the network transition? I would like to know where the network transition comes from… Any doc on that?

On the Network, there’s one D-Link Gigabit Switch (DGS-1005D), one older D-Link Megabit Switch (DFE90-5DX) and one Airport extreme Basestation (configured as a bridge).

Could any of these devices be the cause of my worries and problems you think?

[OD Master]

As you do run NAT on the server I assume both Ethernet interfaces are in use?

Are you running DHCP on the primary? If you do, then it might be that the router / half-bridge modem on the primary is running in DHCP spoofing mode.
This means that the DHCP lease time is just 30 seconds causing the “Network Transition Occured” after each renewal. The short lease is necessary when running on a line with dynamic IP, but with a server you will certainly have a static IP from your provider?

I had the same with a Netgear DG632 ADSL Modem so I simply changed the primary interface to manual with the values that DHCP provided and the messages are gone.

Hope this helps,
Norbert

[XFox]

[QUOTE][u]Quote by: OD Master[/u]

This means that the DHCP lease time is just 30 seconds causing the “Network Transition Occured” after each renewal. The short lease is necessary when running on a line with dynamic IP, but with a server you will certainly have a static IP from your provider?

I had the same with a Netgear DG632 ADSL Modem so I simply changed the primary interface to manual with the values that DHCP provided and the messages are gone.

Hope this helps,
Norbert

[/QUOTE]

This really helped me a lot, thanks Norbert!
Finally I found the cause of those weird messages every 30 seconds.
However, Apple could put a note on this behaviour in the [url=http://docs.info.apple.com/article.html?artnum=303859]article[/url] that suggests to use half-bridge mode! 👿
I’m using a [url=http://www.hamletcom.com/ProductDetails.aspx?sid=f00dac899b914fd39fc18ebad51faa7f&ProductId=3405&CategoryId=18]Hamlet HRDSL640 ADSL Modem Router[/url] and I’ve already tried once to follow your instructions by configuring the primary interface to manual but I ended up with no Internet connection, so I had to revert to using DCHP. I’ll perform another try today.
Meanwhile, do you know if some modem/router implements half-bridge mode in such a way that the server interface is required to be configured in DHCP mode?
I have this doubt because of the former failure and because the [url=http://docs.info.apple.com/article.html?artnum=303859]Apple article[/url] seems to say to configure the server’s interface in DHCP mode… 😐

[XFox]

[QUOTE][u]Quote by: XFox[/u]

I’ll perform another try today.

[/QUOTE]

No way, it didn’t work (for me).
I copied the settings to the manual configuration exactly as it were in the DHCP one, I restarted the modem/router, I restarted the server but nothing made the Internet connection working. I tried the DHCP with manual address, too, but I had to revert to DHCP.
A weird thing is that if I set up the interface in Manual mode the Network Status view shows that I’m connected to the Internet… it lies.
I don’t know if it may be useful but here you are some screenshots:

[b]Network settings control panel in DHCP mode (Internet connection working)[/b]
[img w=467]http://homepage.mac.com/xfox/NetSet/DHCP.jpg[/img]

[b]Network settings control panel in Manual mode (Internet connection [u]not[/u] working)[/b]
[img w=467]http://homepage.mac.com/xfox/NetSet/Manual.jpg[/img]

[b]Network Status view in Manual mode (Internet connection [u]not[/u] working)[/b]
[img w=467]http://homepage.mac.com/xfox/NetSet/Network%20Status%20with%20Manual.jpg[/img]

[b]Network settings control panel in DHCP with manual address (Internet connection [u]not[/u] working)[/b]
[img w=467]http://homepage.mac.com/xfox/NetSet/DHCP%20with%20manual%20address.jpg[/img]

Any idea or suggestion is much appreciated. 🙁

[OD Master]

Hello –

I looked over the screen shots you posted and I see that you have just one name server entered in the manual setup – the private IP of your own server.

When you configure the server using DHCP it will be supplied two name servers via DHCP from your provider. Unfortunately System Preferences don’t show you which ones, the edit field remains just empty. But those are in effect in addition to those you enter yourself.

Now if your server does not have Recursion enabled it will not be able to resolve any external addresses and your Internet connection attempts will fail.

I have three servers configured in my manual setup: my own server followed by the two servers from my provider. My server has recursion enabled so it will work fine but in addition the external server can take over when my DNS fails.

Hope this helps

– Norbert

[XFox]

I have Recursion enabled in my DNS server, too, and I manually edited named.conf to forward all the requests for external domains to the ISP’s DNSes.
I made other several test and the very odd thing is that sometimes it works and sometimes it doesn’t! :rool:
I didn’t manage to work out what causes one behaviour or the other, but I’m sure that the ISP’s DNS servers listing in Network preference pane doesn’t change anything because I got successes and failures with and without them.
I also found that when the “switch” works a subsequent reboot of the server does not break the magic.
I’m really wondering what the hidden ingredient is! 😡
Do you have any suggestion?
I already looked at the system and console logs but I didn’t notice any relevant information.

P.S.
Now let’s see it the server authentication hangs cease, too! 🙂

[XFox]

[QUOTE][u]Quote by: XFox[/u]

Now let’s see it the server authentication hangs cease, too! 🙂

[/QUOTE]

AAAARRGHHHHH!!!!!! 👿

Let’s enter the debug mode (again)… 😥

[XFox]

[QUOTE][u]Quote by: XFox[/u]

Let’s enter the debug mode (again)… 😥

[/QUOTE]

Well, it actually turned out that maybe the switch to manual IP solved the problem. Indeed, we didn’t have any more failure since the one reported in my former post.
However, after we played a bit with the G5 and a new PCI Ethernet card (only to find out that it seems we picked up an incompatible card… more info in a thread I’ll open in the “Questions and Answers” forum), we cannot succesfully switch again from DHCP to manual.
I don’t know what this depends on, we’ll try another router, but meanwhile I configured the present router to use DMZ to forward all the traffic to the server’s IP address.
What are the disadvantages of this solution compared to the half-bridge mode one, if any?
At the moment, it seems it’s working pretty much in the same way (from the user point of view).

[Author]

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