>Date: Fri, 27 Feb 1998 13:54:39 -0500 >From: John E Hein <jhein@fallschurch.esys.com> >To: Wajihuddin Ahmed <wahmed@isb.worldwerx.com.pk> >Subject: Re: cross subnet browsing >Message-ID: <199802271854.NAA10232@lorax.ERA.COM> > >> <snip>>>Another issue I considered when I was having problems was the amount >>of time it took to resolve elections and update browse lists and so >>on. When I was experimenting, I may have been changing smb.conf >>and restarting nmbd too frequently. You may want to give it >>10 minutes to settle between changes. > >>Does anyone have a good idea how long things like that (elections, >>browse list updates, etc.) might take? How long should I have >>to wait to decide that a certain smb.conf setup works or does not >>work with respect to network browsing? >Hmmm. Elections should only take a few hundred milliseconds to resolve. Updates from Master Browser to backup browsers are performed every fifteen minutes. One problem to be aware of is that there is a great deal of anecdotal evidence to indicate that Win95 and Windows3.1 clients frequently contend for the right to act as Master Browsers, even with NT Domain Controllers. In the event of contention, the offending client must be configured NOT to act as a browser server. (MaintainBrowseList=No) You mentioned WINS in conjunction with browsing, specifically, a WINS server's ability to track browser servers. This is a common assumption, but you should be aware that WINS servers do not track master or backup browsers. With regard to browsing, WINS servers are useful insofar as they permit domain controllers to resolve the IP addresses of external domain controllers and permit domain-to-domain browse list exchanges. They also ensure that subnet Master Browsers can direct datagrams to the domain PDC (the Domain Master Browser). Some basic facts: 1. Browsing is, essentially, a broadcast-based service that should not cross the router; 2. Every subnet has a Master Browser determined by configuration or election; 3. Each subnet MB periodically updates the Domain Master Browser (PDC) with a directed datagram (not broadcast); 4. The resource list accumulated by the Domain MB is used to update each of the subnet MBs, thus allowing resource visibility across routers; So, browsing is a broadcast-based service that does not require, or depend upon, the netbios name services provided by a WINS server. Browsing works this way: a client seeking a view of network resources broadcasts a request for a list of backup browsers; the segment master browser responds with a list of up to three backup browsers (also on the same subnet); the client requests a list of available resources from one of the backups (if no response, it moves to the second on the list) and one of the backup browser provides a copy of the last resource list that it received from the master browser. All Windows clients broadcast "I'm alive" messages during the boot sequence, and once every twelve minutes thereafter, to ensure that they are registered with the master browser on their subnet. Any system that boots up and is configured to perform as a master browser will force an election and, if everything works normally, win. Since it has an empty resource list (having just booted) it will broadcast a "registration demand" to which every client must respond within 30 seconds (staggered). With a complete segment list in hand, it will register with the Domain Master Browser (the PDC) and exchange updates, receiving a list of resources known within the Domain. It is also possible to view resources external to the Domain if either the WINS server or PDC have other Domain addresses registered. Now that I've managed to completely confuse the issue, I'll end this thread... - Pete Pete Clark, EDS>