Re: Ip subnet Zero & Ip classess [7:35340]
Ok, try this Ip- classless: allows a router to look for routes classlessly (understands subnets) meaning it will do a longest bit match with routes in your routing table but if after checking for subnets it doesn't find one locally then it follows the default route. With out this command the router would still do a longest bit match but doesn't understand subnets, and would check for a subnet if it is not local to your router it would be dropped. Ip subnet-zero- This allows the use of the zero subnet and the ip addresses in that range. take for instance you have a 10.1.1.0/24 and you decided to break that up into 2 networks. the network would be 10.1.1.64/26 and 10.1.1.128/26 you have lost two networks network 10.1.1.0/26 (.1-.62, 63 is broadcast) and its ip addresses and 10.1.1.192/26 (.193-254, 255 is broadcast) and its ip addresses. PING wrote: >ip classless is used to tell the routing protocols which supports VLSM that >subnet should be sdvertised as part of the route. ip classfull on the other >hand >is used to restrict to use major class subnet mask. > >Nadeem >== > >Arnaldo Gomez wrote: > >>Can someone give a gerneral explanation on these two commands? >> >>ip subnet-zero >>ip-classless >> >>What do they do and why would you use them? >> >>Thanks. >> >>Arnaldo >> >-- > >Ishrat Nadeem Zahid >CCNP >Cisco Systems,Inc. >Chelmsford, MA 01824 Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=35370&t=35340 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Ip subnet Zero & Ip classess [7:35340]
ip classless is used to tell the routing protocols which supports VLSM that subnet should be sdvertised as part of the route. ip classfull on the other hand is used to restrict to use major class subnet mask. Nadeem == Arnaldo Gomez wrote: > Can someone give a gerneral explanation on these two commands? > > ip subnet-zero > ip-classless > > What do they do and why would you use them? > > Thanks. > > Arnaldo -- Ishrat Nadeem Zahid CCNP Cisco Systems,Inc. Chelmsford, MA 01824 Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=35348&t=35340 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Ip subnet Zero & Ip classess [7:35340]
subnet zero lets you do this: ip address 192.168.1.1 255.255.255.252 ip classless lets you do this ip address 192.168.1.1 255.255.0.0 and probably more importantly it will allow a router to forward a packet via a default route even though router is connected to a subnet of the major network your trying to reach, i.e. discontiguous. Dave Arnaldo Gomez wrote: > > Can someone give a gerneral explanation on these two commands? > > ip subnet-zero > ip-classless > > What do they do and why would you use them? > > Thanks. > > Arnaldo -- David Madland Sr. Network Engineer CCIE# 2016 Qwest Communications Int. Inc. [EMAIL PROTECTED] 612-664-3367 "Emotion should reflect reason not guide it" Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=35344&t=35340 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: Ip subnet Zero & Ip classess [7:35340]
Well, From http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/12cgcr/np1_r /1rprt2/1ripadr.htm#xtocid12 : ip classless At times the router might receive packets destined for a subnet of a network that has no network default route. To have the Cisco IOS software forward such packets to the best supernet route possible, use the ip classless global configuration command. To disable this feature, use the no form of this command. Regarding subnet zero, the IOS didn't used to let you assign an address that was part of subnet zero. It wasn't allowed because it could create an address that was the same as the subnet address. Here's a link from cisco with more lovely info about that and the all one's subnet: http://www.cisco.com/warp/public/105/40.html -Original Message- From: Arnaldo Gomez [mailto:[EMAIL PROTECTED]] Sent: Wednesday, February 13, 2002 1:45 PM To: [EMAIL PROTECTED] Subject: Ip subnet Zero & Ip classess [7:35340] Can someone give a gerneral explanation on these two commands? ip subnet-zero ip-classless What do they do and why would you use them? Thanks. Arnaldo Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=35343&t=35340 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: Ip subnet Zero & Ip classess [7:35340]
This is definitely a topic where you should search the archives. There have been some excellent discussions in the past that have resulted in some great explanations of each of these commands. It would be better for you to read them than to have the original posters type them in all over again. :-) Regards, John >>> "Arnaldo Gomez" 2/13/02 2:44:37 PM >>> Can someone give a gerneral explanation on these two commands? ip subnet-zero ip-classless What do they do and why would you use them? Thanks. Arnaldo Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=35342&t=35340 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
