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Subnets and Network Browsing?
photozz asks: "We are on a large network (1000+ nodes) with a mix of everything, Wintel, Unix, Linux and Mac. Lately, we have been getting broadcast storms that kill the network. Our solution is to subnet everything with routers, thus killing broadcast trafic. BUT, this will limit Windows browsing on the network to each segment. Installing Brouters will just give us the same packet storm problems we had before. How can we stop broadcast trafic while enabling Netbios resolution acros routers?"
Here's what you do.
Set up a primary and secondary WINS server. Ideally they should be on separate subnets.
On each subnet designate two machines to be the browse masters. These should be rebooted as little as possible and should definitely NOT BE user workstations. They should be running NT or a recent version of Samba and the Browser must be turned on. Also, the Computer Browser should be running on all domain controllers.
On _every_ other machine, turn off the computer browser. Also, set each machine to be a P-node. The easiest way to accomplish this is to assign IP's using DHCP and set the Netbiod Node Type to 0x2. Make sure all of these systems have the primary and secondary WINS servers assigned.
You must strictly control all new machines that come onto the network and make sure that no new browsers are allowed to come up on the network.
If you go to all of this trouble, the reward you will receive is extremely fast and reliable network browsing across subnets. I know because I've done it on a 1500 node WAN. It takes a lot of discipline that most IT departments don't have or can't enfore but it's worth the trouble in my opinion.
I run a UNIX/Samba LAN. I use only UNIX/Samba for file/print services. We use WINS on all our clients, including talking to other subnets.
Unfortunately, I have one NT Server for a SQL application (that I fought, and lost, to keep off my network -- only 3 people use it). I do not use named pipes on it at all and tell it to use WINS for NetBIOS resolution. But the f'er sends out more broadcasts that all other (50) systems combined (an average of ~10/second). I have tried tweaking this thing 10 ways to Sunday and cannot get it to stop the chatter (and yes, I've told it to NOT be the local master).
Case in point, if get NT Servers off your network, you'll cut the chatter several times over. I'm much more of an expert at Samba than NT, but after 8 years experience with NT, I think I know somewhat of I'm doing (although I'll take any suggestions at this point ;-).
P.S. I was the contributing author on Samba Unleashed and wrote Chapter 33 on "Cross Subnet Browsing" (which was a last second rush job, otherwise I would have added info to fix exactly the issues you are having by replacing NT with Samba). IMHO Samba is just so much better at running large WANs with multiple subnets!
-- Bryan "TheBS" Smith
-- Bryan "TheBS" Smith
Independent Author, Consultant and Trainer
No. THat lets anyone resolve any name, but does not provide 'brosable' lists of all hosts on the network.
Just as DNS does not provide a list of who is where when.
I can't believe that you are running 1000+ nodes and don't know about WINS. Try buying a book and reading up on WINS.
Have you used a sniffer to see what this "broadcast storm" traffic is? That would do for a good start. A description of the issue other than "kill the network" would do more good as well. What kind of byte/sec and packet/sec counts are we seeing on the media?
Assuming it is broadcast related: Your 'doze boxes need to be using "H-Node" name resolution for their cruddy NetBIOS name resolution. You need WINS servers. You need to disuse protocols that are broadcast intensive.
To the guys that are saying "install a switch"-- apparently there's an understanding issue w/ regard to what a switch does. A layer-2 switch won't help a bit in this case-- just like the poster said (referring to bridging routers). An analysis of what the traffic on the wire is would be a great first step. Then, intelligent decisions can be made to address the problem. Layer-3 switching might be a potential solution, depending on what the traffic is.
Unless you're using layer-3 entities inside of switches, your router based solution is going to do more than mess up NetBIOS name service-- it'll slow everything down to a crawl. Most low-end routers don't even come close to wire-speed.
I had a customer swearing to me that they were having "broadcast storms" because they were getting massive numbers of collisions on a shared-media LAN. We took a look at it w/ a sniffer and discovered that broadcasts played no part in it. They were doing large file transfers to a machine that was dual-homed on the same physical NIC, and the machine was thrashing packets on and off the wire, "routing" the packets to two hosts that were in different subnets, but on the same media. Duh.
Don't assume you know what your problem is unless you know what your problem is...
The Attitude Adjuster, I hate me, you can too.
Without WINS:
Q117633 - How Browsing a Wide Area Network WorksThe proper way to do it, though, would be to set up a WINS server and WINS Proxy agents:
w inNT Mag article on WINS - actually, do a search on this site for "WINS" and you'll find several other usefull articles. Q121004 - WINS Proxy Agent FunctionalityAlso usefull:
Q142692 - Minimizing WAN Traffic-jerdenn
OKiedoke, but this would involve converting 250+ servers and databases. can we say political suicide? We just signed (Not me, someone else..)an enterprise level agreement with $MS, so were stuck.
Dirty Pirate Hooker
remove the hubs and go to swiches, should cut down on broadcast trafic, and increase your speed.
Dirty Pirate Hooker