NetBIOS names vanish from network intermittent..

[fishleg]

Hi,
We have a customer who scans to smb via hostname. Each PC has its own shared folder 3 are wired 8 are connected wirelessly.

Intermittently the 8 will appear to vanish from the copier when it tries to find them via their NetBIOS name. Try 30 mins later absolutely fine. They don't drop off the network as they can be pinged from any of the wired machines while this is happening.

Anyone think of any scenarios why this might be happening?

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[NeoMatrix]

More info.
Win version ?
Internet Security sofware ?
Single Modem or PC Server as DNS





Sent from Nokia Mobile.

[Iowatech]

I don't know how much this will help, but a sometimes when I see a problem arise and then mysteriously disappear it can caused by the power being supplied to the machine by the outlet it is plugged into varying by over 10%.
Something you might want to check out.

[slimslob]

How old is the wireless router? What is the bandwidth of the wireless? Wireless bandwidth specs: 2 Mbps 802.11, 11 Mbps 802.11b, 54 Mbps 802.11a, 54 Mbps 802.11g, 300 Mbps 802.11n, newest 802.11ac 450 Mbps on 2.4 Ghz and 1300 Mbps on 5 Ghz.

If by vanishing you mean that they get an error trying to scan, they might be getting time outs caused by insufficient bandwidth to handle the wireless network traffic during peaks of wireless usage.

Wireless Standards: 802.11a, 802.11b/g/n and 802.11ac

See NeoMatrix post in "Connectivity, wireless router or my Ricoh Image Scanner is200e" concerning power management for wireless devices on Windows computers. Wireless interfaces on idle computers might be shutting down.

[qbert69]

...just to be sure, go into "device manager" under "computer management" and for the wi-fi or ethernet adaptor, make sure that it is not set to go to sleep to save energy! Sometimes the "energy saving" function can cause a variety of issues. I have set up some virtual machines at our office with VirtualBox and if the ethernet adapter went into the energy saving mode, it would disconnect the virtual machine and wreak havoc!

...just my 2 cents worth!

[fishleg]

All windows 7 machines, 1 router. Its just strange because everything else works when its not visible to the photocopier via hostname. You could be onto something with the power save though I wired one of the wireless PC's up and it never dropped off....

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[slimslob]

All windows 7 machines, 1 router. Its just strange because everything else works when its not visible to the photocopier via hostname. You could be onto something with the power save though I wired one of the wireless PC's up and it never dropped off....

Sent from my Nexus 5 using Tapatalk

The power save setting only affects the wireless interface. The wired LAN port is always active.

[JVergin]

Had a similar situation with one of our main office customers, much more intermittent though (either that or the customer ignored it most of the time). Every few months customer could call for the same problem. A small office with only 3 desktop computers and 1 laptop all connected wirelessly. Customer is randomly not able to scan. Sometimes it's everyone, sometimes only one, or two, 10 minutes later the two that didn't work now work, and the two that worked now don't work, etc... Never has any print problems.

Since I only had one shot at it, I tested just about everything I could think of and tried to eliminate every scenario I could because of course everything was working fine while I was there. After the other two techs ruled out all of the normal stuff, These three things stood out to me and one of them may be your fix.

1) Upon sending a constant ping to the copier, I noticed every now and then it would time out. Not very often at all, but it would time out nevertheless. Also had another PC pinging google.com. Same result. I actually was able to talk to their cable provider, who also provided their modem/wireless router, and they agreed to come out and replace the modem/router. (cables were already tested as OK, and replaced anyway to rule it out)
2) I noticed the copier's IP was inside the DHCP range. Even though they only have a few computers, maybe someone's cell phone or tablet is taking the copier's IP. So, I changed the copier's static IP to something outside of the DHCP range.
3) Since it was a small office, I went ahead and set all computers to a static IP address and had the copier send to their IP address rather than their hostname.

Customer hasn't called back since. Usually I don't make such changes all at once with intermittent issues, I'll do them one at a time so I know which one fixed it, but the customer was getting frustrated and I'm not able to keep going there, so I shotgunned it.

Hope this helps!

[NeoMatrix]

...Random snip....Customer hasn't called back since. Usually I don't make such changes all at once with intermittent issues, I'll do them one at a time so I know which one fixed it, but the customer was getting frustrated and I'm not able to keep going there, so I shotgunned it.Hope this helps!

Would love to see a list of the previous actions you took. Please keep us up to date with your findings.I'm doing checks with WinXX.X QOS packet scheduler and modem UPnP timings. I've also noticed the odd dropped UDP packets .... Nothing to report as yet...

[ApeosMan]

I had an issue the other week where I was getting NetBIOS host name conflicts. The reason was because the maximum character limit is 16 and each device would have to truncate their NetBIOS name to be at least 16 characters if it was over the limit. Because most of the NetBIOS host names were similar, some devices would truncate to the same name causing a conflict.

Ended up telling the I.T. rep to re-think their NetBIOS host name conventions or just leave it as the devices default NetBIOS name and just rely on DNS names instead.