Learn how to a build a cloud-first strategyRegister Now

x
?
Solved

Communication Problems between computers on switched network

Posted on 2015-02-03
4
Medium Priority
?
133 Views
Last Modified: 2015-02-05
I have a single subnet network that consists of two buildings. One building has a has a Netgear FS726T Smart switch and the other has a Netgear FS750T2 Smart switch. The two switches are connected by fiber. The server on the network is a Windows 2008 SBS which hosts the DNS and DHCP servers. This setup has worked fine for the past five years. Suddenly, yesterday, five computers where not able to connect to the servers, internet etc. I tried restarting all the equipment with no success. This morning, they are suddenly able to connect again. However, there are still communication issue between some computers. For example, I am not able to ping some of the computers in building two but I am able to ping my computer from those machines. I am at a loss as to what to check. Any suggestions?
0
Comment
Question by:Robcarter10
  • 2
  • 2
4 Comments
 
LVL 71

Accepted Solution

by:
Qlemo earned 2000 total points
ID: 40586726
The latter might result from Windows Firewall reactivating or switching back to not allow incoming connections. A ping from those machines will work then, but not to them.

Yesterday, has there been anything those 5 machines had in common? Were they on the same building, same switch?
0
 

Author Comment

by:Robcarter10
ID: 40586750
They were on the same switch in the same building. There was a variety of Firewalls and OS involved. There was not policy changes made to any of these machines. I have been able to remote desktop to all of these machines in the past. My initial thought is that it is the switch but I do not know what a switch would stop allowing data to certain ports.
0
 
LVL 71

Expert Comment

by:Qlemo
ID: 40586794
Ports can get blocked by a managed switch if there is too much going wrong on that port. Broadcast storms, loops, hardware protocol errors, for example. This could effect other ports as well, but would than count as failure of the switch.

See if you can get device and port statistics from that switch, in particular error counts.
0
 

Author Comment

by:Robcarter10
ID: 40587112
I tried disabling the firewall on one of the computers that i cannot ping and was able to ping it. I didn't even consider this to be an option because I have not changed any configuration on the firewall and have never had an issue connecting to those machines. Not to mention, some of them are running different AV/Firewall. I still don't know if this would have caused the issue I had yesterday though where the computers were not able to access anything on the network at all. Unfortunately, I was off sick so I could not try that and they were working before I arrived today.
0

Featured Post

Prep for the ITIL® Foundation Certification Exam

December’s Course of the Month is now available! Enroll to learn ITIL® Foundation best practices for delivering IT services effectively and efficiently.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

If you’re involved with your company’s wide area network (WAN), you’ve probably heard about SD-WANs. They’re the “boy wonder” of networking, ostensibly allowing companies to replace expensive MPLS lines with low-cost Internet access. But, are they …
This article explains the fundamentals of industrial networking which ultimately is the backbone network which is providing communications for process devices like robots and other not so interesting stuff.
Michael from AdRem Software outlines event notifications and Automatic Corrective Actions in network monitoring. Automatic Corrective Actions are scripts, which can automatically run upon discovery of a certain undesirable condition in your network.…
Michael from AdRem Software explains how to view the most utilized and worst performing nodes in your network, by accessing the Top Charts view in NetCrunch network monitor (https://www.adremsoft.com/). Top Charts is a view in which you can set seve…

810 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question