IP CEF - explanation required [7:4505]
I have been asked by my manager to add the ip cef command to the 3 x 2600 router configs, instead of configuring HSRP on two of them. All I know about this is the syntax which I checked on the doc cd and what it stands for: Cisco Express Forwarding. I do not understand what this is actually doing, and how it works, is it load balancing in some way? Can anyone pls help, I hate putting commands on, which I do not know the impact on the network/router/memory etc in a live environment. Thanks Rashid Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=4505&t=4505 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: IP CEF - explanation required [7:4505]
hi, HSRP ,this is used to setup a Backup router to take-over when the main router fail`s...that is all...it can do some load balalncing (of a sort) although not really you use a virtual ipp address to represent both routers and the HSRP process just acts as a virtual (switch-box) moving packets from one router to the other CEF this is a technique used by cisco routers to switch packets quickly.. what i mean is that, in a router with CEF ,instead of doing a destination lookup for every single packet (the routing) then moving the packet to the outbound interface (the switching) CEF uses a cache to route once switch many..once it finds a route for a packet it keeps records in an mtrie(don`t worry about the name) and adjancency (can`t spell) table. and then uses this info to move (switch ) any new packets bound for that same destination directly to the outbound int.. these two technologys are NOT interchangeable... HTH steve >From: "Rashid Lohiya" >Reply-To: "Rashid Lohiya" >To: [EMAIL PROTECTED] >Subject: IP CEF - explanation required [7:4505] >Date: Tue, 15 May 2001 04:45:22 -0400 > >I have been asked by my manager to add the ip cef command to the 3 x 2600 >router configs, instead of configuring HSRP on two of them. > >All I know about this is the syntax which I checked on the doc cd and what >it stands for: Cisco Express Forwarding. > >I do not understand what this is actually doing, and how it works, is it >load balancing in some way? > >Can anyone pls help, I hate putting commands on, which I do not know the >impact on the network/router/memory etc in a live environment. > >Thanks > >Rashid >FAQ, list archives, and subscription info: >http://www.groupstudy.com/list/cisco.html >Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] _ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=4512&t=4505 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: IP CEF - explanation required [7:4505]
Looks like what you said is multilayer switching. Can we use mulitlayer switching and CEF inter-changeably? jp ""Stephen Skinner"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > hi, > > HSRP ,this is used to setup a Backup router to take-over when the main > router fail`s...that is all...it can do some load balalncing (of a sort) > although not really > you use a virtual ipp address to represent both routers and the HSRP process > just acts as a virtual (switch-box) moving packets from one router to the > other > > CEF this is a technique used by cisco routers to switch packets quickly.. > > what i mean is that, in a router with CEF ,instead of doing a destination > lookup for every single packet (the routing) then moving the packet to the > outbound interface (the switching) CEF uses a cache to route once switch > many..once it finds a route for a packet it keeps records in an mtrie(don`t > worry about the name) and adjancency (can`t spell) table. > and then uses this info to move (switch ) any new packets bound for that > same destination directly to the outbound int.. > > these two technologys are NOT interchangeable... > > > HTH > > steve > > > >From: "Rashid Lohiya" > >Reply-To: "Rashid Lohiya" > >To: [EMAIL PROTECTED] > >Subject: IP CEF - explanation required [7:4505] > >Date: Tue, 15 May 2001 04:45:22 -0400 > > > >I have been asked by my manager to add the ip cef command to the 3 x 2600 > >router configs, instead of configuring HSRP on two of them. > > > >All I know about this is the syntax which I checked on the doc cd and what > >it stands for: Cisco Express Forwarding. > > > >I do not understand what this is actually doing, and how it works, is it > >load balancing in some way? > > > >Can anyone pls help, I hate putting commands on, which I do not know the > >impact on the network/router/memory etc in a live environment. > > > >Thanks > > > >Rashid > >FAQ, list archives, and subscription info: > >http://www.groupstudy.com/list/cisco.html > >Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > > _ > Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=4518&t=4505 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: IP CEF - explanation required [7:4505]
CEF also allows you choose whether to load balance per packet or per destination. Fast switching only allows per destination. Also, the first packet that is CEF switched does not have to be process switched, fast switching requires that the first packet be process switched so that it can build the cache entry. -Original Message- From: Jeongwoo Park [mailto:[EMAIL PROTECTED]] Sent: Tuesday, May 15, 2001 8:28 AM To: [EMAIL PROTECTED] Subject: Re: IP CEF - explanation required [7:4505] Looks like what you said is multilayer switching. Can we use mulitlayer switching and CEF inter-changeably? jp ""Stephen Skinner"" wrote in message [EMAIL PROTECTED]">news:[EMAIL PROTECTED]... > hi, > > HSRP ,this is used to setup a Backup router to take-over when the main > router fail`s...that is all...it can do some load balalncing (of a sort) > although not really > you use a virtual ipp address to represent both routers and the HSRP process > just acts as a virtual (switch-box) moving packets from one router to the > other > > CEF this is a technique used by cisco routers to switch packets quickly.. > > what i mean is that, in a router with CEF ,instead of doing a destination > lookup for every single packet (the routing) then moving the packet to the > outbound interface (the switching) CEF uses a cache to route once switch > many..once it finds a route for a packet it keeps records in an mtrie(don`t > worry about the name) and adjancency (can`t spell) table. > and then uses this info to move (switch ) any new packets bound for that > same destination directly to the outbound int.. > > these two technologys are NOT interchangeable... > > > HTH > > steve > > > >From: "Rashid Lohiya" > >Reply-To: "Rashid Lohiya" > >To: [EMAIL PROTECTED] > >Subject: IP CEF - explanation required [7:4505] > >Date: Tue, 15 May 2001 04:45:22 -0400 > > > >I have been asked by my manager to add the ip cef command to the 3 x 2600 > >router configs, instead of configuring HSRP on two of them. > > > >All I know about this is the syntax which I checked on the doc cd and what > >it stands for: Cisco Express Forwarding. > > > >I do not understand what this is actually doing, and how it works, is it > >load balancing in some way? > > > >Can anyone pls help, I hate putting commands on, which I do not know the > >impact on the network/router/memory etc in a live environment. > > > >Thanks > > > >Rashid > >FAQ, list archives, and subscription info: > >http://www.groupstudy.com/list/cisco.html > >Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] > > _ > Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html > Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED] Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=4523&t=4505 -- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]