Brief random network outages

Hi
We have a networking issue that I hope someone may be able to help me with.
We run a Windows domain - single domain, single subnet. Three domain controllers: Windows 2012 R2 Standard, Windows 2008 Standard (32bit) and Windows Server 2003 Standard. The Win 2008 DC holds all the FSMO roles. DNS is setup on the 2008 and 2012 DC's
with the 2008 DC having a secondary DNS server installation. DHCP is setup on the 2008 DC. The 2003 server only functions as a DC - no roles apart from that are installed and it will be demoted very soon.
Two member servers: Windows Storage Server 2008 (64bit) and Windows 2012 Standard. The Storage server hosts 99% of our data with the other 1% being on the 2008 DC. Two email server software installations (not Exchange) - one on the storage server and one
on the 2012 R2 member server. NPS Routing and Remote Access is configured on the 2012 member server to handle VPN connections.
35 client PC's: 34 run Windows 7 and one runs Vista.
We have two Draytek routers on the network - one acts as the gateway to the Internet and the other provides wireless coverage. There are two networked printers - a Ricoh MFD 'workgroup' printer and a small mono Brother.
Network shares are accessed via DFS. The Servers, the Ricoh printer and routers have static IP's, most of the clients and the Brother printer use DHCP.
All cables terminate at one of two patch panels which then feed to one or more switches. Small desktop switches are used to expand the network where needed. The network is divided into two segments, hence two patch panels, but both run under the same 192.168.0.xxx/255.255.255.0
subnet.
Before we upgraded all our computers to Windows 7 the network was fine. The present network was built using CAT5 cabling in 2004 (we'd used BNC before that). We rarely had any network issues and when we did it would affect all clients. When
I first introduced Windows 7 it was on three PC's and one or more of them would randomly have problems accessing the network and Internet.
When I upgraded all our machines to Windows 7 we are seeing one or more machines experiencing network problems most days.
What happens is the (any) computer will suddenly stop - Applications accessing files across the network e.g. email and Access will hang and report as (not responding) and the 'busy' cursor appears. Try and save an office document and the busy cursor appears
and the application hangs. The Start menu is not accessible - for example I always have my Taskbar hidden and when this happens on my machine moving the mouse to the bottom of the screen does nothing, the Taskbar stays hidden. Sometimes, the Taskbar may
appear, but nothing happens when the Start button is clicked. When trying to access shared folders via Computer the green bar slowly moves through the Address Bar and after a while it reports the share is not accessible. The affected computers are also unable
to open any web pages.
The hang will last for anything from 20 secs to a minute or more after which the computer will continue operating normally. On very rare ocassions the the computer will not recover after 10mins or more and I have to force a shutdown but I assume this is
not directly related to the issues I am seeing.
The short outages are completely random and leave no trace of a problem in the System or Application Logs. When a machine does not recover (which is very rare) the System Log reports that a DNS server could not be reached.
This will happen on a single PC and others will be fine. But, it may affect several PC's over the course of a day.
When the outage happens I can Winkey+R, open cmd.exe and successfully ping the DNS servers by IP and name.
All the systems are up to date. I ensure that Windows Updates are installed on the Servers when they are released and the clients are updated the next day via WSUS.
I am pretty sure that this is also affecting Active Directory. I am seeing transient errors on the Domain Controllers where, for example, a Global Catalog can not be contacted. Both DC's are GC's and when I run nltest to test the connection to a GC within
30 minutes of the error being reported the test passes. I assume the servers are also experiencing these random outages.
The problem I have is that because they are random and because, on the clients at least, no errors are logged I cannot reproduce the problem and have no idea what may be causing the issue.
The problem is not a general network issue as it randomly affects one client at a time - if was a general network problem I would expect all the clients to lose connectivity.
Has anyone else seen a similar issue and know what the cause was, please?
Thanks

how old is the server?
How old is your network switches?
Any computer or server with NIC or network switches going south, may cause the intermittent issue.
They may flood the network with packets thus hang the system.
Every second counts..make use of it. Disclaimer: This posting is provided AS IS with no warranties or guarantees and confers no rights.
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Network speed affected by large file copy operations. Also, why intermittent network outages?

Hi
I have a couple of issues on our company network.
The first is thate a single large file copy imapcts the entire network and dramatically reduces network speed and the second is that there are periodic outages where file open/close/save operations may appear to hang, and also where programs that rely on
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Ordinarlily we work with many files
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What have you checked for resource usage during one of these copies of a large file?
At a minimum I would check Task Manager>Resource Monitor. In particular check the disk and network usage. Also, look at RAM and CPU while the copy is taking place.
What RAID level is there on the file server?
There are many possible areas that could be causing your problem(s). And it could be more than one thing. Start by checking these things. And go from there.
Hi, JohnB352
Thanks for the suggestions. I have monitored the server and can see that the memory is nearly maxed out with a lot of hard faults (varies between several hundred to several thousand), recorded during normal usage. The Disk and CPU seem normal.
I'm going to replace the RAM and double it up to 12GB.
Thanks! This may help with some other issues we are having. I'll post back after it has been done.
[Edit]
Forgot to mention: there are 6 drives in the server. 2 for the OS (Mirrored RAID 1) and 4 for the data (Striped RAID 5).

Database Replication never fall back over MAPI Network in case of dedicate network outage

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Twitter!: Please Note: My Posts are provided “AS IS” without warranty of any kind, either expressed or implied.

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Network outage/problem this morning?

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Message was edited by: Rottsko

After recovering from a network outage firefox5 takes much longer time to be able to connect to web pages ( vs chrome).

system is running windows 7, ATT DSL .

Maybe try this, i am not sure that it will resolve the problem, but it is worth trying anyways.
http://social.technet.microsoft.com/Forums/en-US/w7itpronetworking/thread/eef49e64-157c-4082-8e80-52e48309691f
Hi All,
I've seen this problem multiple times, especially with Windows 7 64-bit versions and Enterprise edition. The source of the problem appears to be the Bonjour service that is installed in the background and set to "Automatic" when installing certain 3rd
party applications. Apple applications like iTunes and Adobe applications like Acrobat Professional and Creative Suites have been known to cause this problem. I've also seen virtualization software like VMWare and VirtualBox cause similar issues
with network adapters.
The solution in most of the cases I've come across has been to stop and disable the Bonjour service. The Bonjour service also masquerades as a service with a name of the format "##Id_String1.6844F930_blahblahblah". Here's how to disable this service
in Windows 7:
Right-Click on Computer > Select 'Manage'
Expand the 'Services and Applications' section in the bottom of the Left-Nav dialog and Select 'Services'
Sort the Services list by name and look for either "Bonjour" or the "##Id_String..." name mentioned above
Right-Click on the service and select 'Properties'
Click the 'Stop' button to stop the service
Select 'Disabled' from the 'Startup type' drop down list
Click 'Apply' and then 'OK'
Reboot your machine and see if the "Multiple Networks" issue is resolved. If so, you should have internet connectivity again.
Hope this helps.
cheers,
Aaron

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OK this is now driving me insane and i think i'm going to have to take the ATV back for a refund.
The box just keeps freezing and hangs until the Apple logo comes up with the reset menu. I've run diagnostics but it never finds anything wrong and i swear i'm about to put my foot through this thing.
The symptoms are all over the place.. It first started dropping off the wireless network and freezing when streaming content from my Mac so in the end i cabled it, seems to have sorted it for a while and now if iTunes updates itself at all the ATV stops what it's doing and hangs. This happens on streaming music or internet radio and i've given up on streaming iTunes video content.
It seems the only way i can get it to play anything is with a full sync over cat5 and this is of course NOT what i wanted it for.
Anyone for any ideas? I've stopped it syncing now automatically with iTunes to see if that's the issue and i'm waiting to see the outcome of that.
I see people are having hdmi switching issues so it maybe worth noting this is connected using HDMI to DVI.
TIA

Many people are seeing problems since latest software updates but they're still probably in the minority.
Are you running 3.0 or 3.01?
I'd advise you to send feedback here:
http://www.apple.com/feedback/appletv.html
Apple need to know about such issues.
HDMI has it's own problems in some instances, the issue with DVI is that you may fall fould of HDCP protection issues with purchased content. Component may be a better option, either way you'd need a separate audio feed from AppleTV.
CAt5 is not practical by the sounds of it.
I've always maintained that AppleTV/iTunes for some reason do not handle brief wireless network outages gracefully - and once a connection is lost it does not always automatically re-establish when the cause of the interruption has passed (eg RF interference from microwaves/landline cordless phones/neighbouring networks etc).
Wireless is inherently unreliable in my opinion but when it works it can do so nearly flawlessly.
An option I use on some of my devices is mains powerline networking adapters (I use Devolo, there are many other vendors eg Netgear, Belkin, generic etc) and I find them very effective - might be something to consider trying, though it would only solve the issue if network interruptions not software/hardware faults were the cause.
Good luck.

Improved Handling of Brief Outage

Since this forum mostly has to do with problems, I thought I'd add kudos to the File and Font Sync team for improvements in your handling of brief file syncing outages.
I experienced a week or more long lack of ability to sync my Typekit fonts and files. This was fixed for with with the version 232 update to Creative Cloud Desktop app. (Thanks also to the Typekit team who provided constant support during this period.)
This morning, I experienced a brief outage on both of my computers (fonts disappeared, file syncing unavailable). After about a half hour, I was pleased to see that the syncing and fonts returned automatically so I see you're making some progress. Thanks for your efforts. I'm sure it's not an easy job.

Hi Steve,
Glad to hear you're seeing improvements and thanks for the kind words. Also, you're help in the forums has been great. Please let us know if you run into anything else: [email protected]
Cheers,
Ben

Brief random network outages

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