Jump to content


Register a free account to unlock additional features at BleepingComputer.com
Welcome to BleepingComputer, a free community where people like yourself come together to discuss and learn how to use their computers. Using the site is easy and fun. As a guest, you can browse and view the various discussions in the forums, but can not create a new topic or reply to an existing one unless you are logged in. Other benefits of registering an account are subscribing to topics and forums, creating a blog, and having no ads shown anywhere on the site.

Click here to Register a free account now! or read our Welcome Guide to learn how to use this site.


Troublesome Network

  • Please log in to reply
1 reply to this topic

#1 christopherpfinch


  • Members
  • 10 posts
  • Local time:09:52 PM

Posted 25 August 2015 - 04:26 PM

Hi everyone,


I've been tasked with the lovely job of fixing our network issues. 


Here's some background:


2 Domains:

  • Teacher - 100 Computers and iPads total.
  • Students - 600 Computers and 800 iPads Maxed.
  • It probably resides around 1,000 users at once.


  • Assume all users connect through wireless.
  • All users are on the same VLAN - We will call it VLAN 200.
  • Interference - 2.4 has a ton of interference with the TWC and ATT hotspots outside of our WIndows.


  • There are 2 authentication servers.
    • Teacher-DC which is on VLAN 150.
    • Student-DC which is also on VLAN 150 (I think this directs the students to Teacher-DC for authentication).


The printers and all other servers are on VLAN 150.


My assumptions as to the cause of the issues.

  • VLAN 200 is overloaded.
  • VLAN 150 is overloaded and bombarded with packets that are crossing the subnet.
  • The WiFi is being interfered with by the hotspots.
  • We don't connect the switches with crossover cables... just B wiring ethernet.

I need help!


I'm new to networking and my boss won't answer questions because I dared to ask if we should break up the network into smaller subnets. We could build a DC for each grade and break up VLAN 200 into 200 (Teachers) 201 (Freshmen) 202 (Sophomores) 203 (Juniors) 204 (Seniors) and put their DC's on their respective VLAN.


I feel this could alleviate the possibility of bottlenecks at 150 and 200.


Please let me know if I'm on the right track. I only know networking from a book, and this is my first real hands on experience. Aside from learning, I really want to shut him up.  :axe:


Any help is welcome!




Edited by christopherpfinch, 25 August 2015 - 04:44 PM.

BC AdBot (Login to Remove)


#2 Wand3r3r


  • Members
  • 2,027 posts
  • Local time:09:52 PM

Posted 26 August 2015 - 10:56 AM

Not trying to be harsh but the first setup was done by someone who didn't understand networking or AD setup.


Please review the comments below:


2 domains only added complexity.  I will bet they are standalone DC's with no AD failover

No mention of file servers which tells me the DC's are the file servers.  Great way to lose everything.

1100 wifi users requires a pretty advanced wifi setup /distribution of APs.  There should be as many wired connections as possible

Subnetting needed to be done in conjunction with vlans but this depends on your physical topology.  Doesn't make much sense to have lots of vlans if you have lots of switches for example.

You don't connect switches any more with xover cables.  They should be connected by uplink ports which usually run a higher throughput rate then the ports do.

You don't guess at bottlenecks.  You look at your physical design and then at your logical design.  Between the two you can foresee where bottlenecks can happen and you design to prevent that.

The proposed vlans are confused with groups/OU's.  Vlans are to provide security or specific broadcast domains.  Juniors are not a broadcast domain for example.


I would suggest a top and bottom approach to your issues

1. address the domain and DC issues

2. look at /redesign the physical topology to eliminate/reduce bottlenecks. Then properly identify your broadcast domains and decide the best way of addressing them.

Edited by Wand3r3r, 26 August 2015 - 05:20 PM.

0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users