RE: Netbios on Wan [7:61249]
Priscilla, Thanks for clearing that, infact I was not sure about enableing Directed broadcast on a interface with IP helper-address. Thanks for the explanation. Sarkis Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=61322&t=61249 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Netbios on Wan [7:61249]
Don't enable ip directed broadcast. There's no need to and it's bad practice, from a security point of view. Enabling ip directed broadcast allows the router to forward directed broadcasts. For exmaple, if someone from another network pinged 10.0.0.255, a router that has an interface on 10.0.0.0/24 would forward that packet out that interface, if you enabled directed broadcasts. That's bad. This has nothing to do with a router sending a packet to a broadcast address when you configure ip helper address. Karagozian Sarkis wrote: > > Yes, According to Cisco BSCN Book (Building Scalable Cisco > Networks) > pages 88-91. > and Exam Cram book ACRC (Advanced Cisco Router Congirn) pages > 46-47. > mentions using ip helper-address to forward to a directed > broadcast address (ie. for this specific subnet 172.16.2.0 > where the servers reside) If the book really says that, I would guess that the language got the author in trouble. IP helper address isn't just generic forwarding, like a router does normally. It's telling the router to be a relay agent or gateway of sorts, which is different. With DHCP, the client sends to 255.255.255.255. The router can forward that to 172.16.2.255, for example. Note that's different from the example above of the router forwarding a packet. See the extra work it's doing here? It's acting like a gateway with an advanced atypical job that is not its normal forwarding job. > > Remember, on the Interface you also need to enable the command: > ip directed-broadcast > (which is disabled by default on rel 12.0 and later) Yes, and it's a good thing that ip directed broadcast is disabled by default and you shouldln't change it in most cases, certainly not just to get DHCP to work. HTH ___ Priscilla Oppenheimer www.troubleshootingnetworks.com www.priscilla.com > > > So here are the commands you need to add on the Remote Router > interface: > > Interface e0 > > ip helper-address 172.16.2.255 > ip helper-address 172.16.3.2 > ip directed broadcast > > So Braodcasts arriving on e0 will be forwarded to all servers > on the 172.16.2.0 subnet and to the designated server > 172.16.3.2. > > Hope this helps. > > Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=61316&t=61249 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Netbios on Wan [7:61249]
Yes, According to Cisco BSCN Book (Building Scalable Cisco Networks) pages 88-91. and Exam Cram book ACRC (Advanced Cisco Router Congirn) pages 46-47. mentions using ip helper-address to forward to a directed broadcast address (ie. for this specific subnet 172.16.2.0 where the servers reside) Remember, on the Interface you also need to enable the command: ip directed-broadcast (which is disabled by default on rel 12.0 and later) So here are the commands you need to add on the Remote Router interface: Interface e0 ip helper-address 172.16.2.255 ip helper-address 172.16.3.2 ip directed broadcast So Braodcasts arriving on e0 will be forwarded to all servers on the 172.16.2.0 subnet and to the designated server 172.16.3.2. Hope this helps. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=61289&t=61249 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Netbios on Wan [7:61249]
Hi Frederico, Yes, You you need to use : Interface e0 (for eaxample on remote router) ip helper-address 172.16.2.255 (to reach all servers on subnet 172.16.2.0 from the remote routers) Hope this helps Sarkis Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=61270&t=61249 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Netbios on Wan [7:61249]
yes, you will have to use a separate entry for each. -Original Message- From: Han Chuan Alex Ang [mailto:[EMAIL PROTECTED]] Sent: Thursday, January 16, 2003 10:28 PM To: [EMAIL PROTECTED] Subject: Netbios on Wan [7:61249] hi, wondering if it is possible to configure more than 1 ip for IP helper address Author: Amazing () Date: 01-17-03 01:18 ip helper address on the ethernet interface of the remote router. this will change the nbns broadcast to a unicast directed at the remote lan ""Frederico Madeira"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > Hellow, > > how i configure an 2600 router to permit acess for network neighborhood to > computers on the lan, in other words, how i make to see all computers of > my WAN in network neighborhood of windows explore ? Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=61254&t=61249 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
