Re: utilization rate calculation
I'll try to restate this in a way that makes sense, but the text you quoted says it pretty well. The MIB data you are accessing is stored as a counter that increments for each byte transmitted and received. Let's say you polled the router and got this information: InOctets: 543980 OutOctets: 234095 Does that tell you anything? Not really. However if you wait a minute and poll it again you could see the amount of traffic in and out of that interface over a period of time, which gives you a rate. A single poll will not give you any usefull information. To get a rate, you need to sample the data over time. In this case the data is stored in bytes so you multiply times eight to get the rate in bits per second. Does that help? If not, I'll try again later after some more coffee. John >>> "Luong, David" <[EMAIL PROTECTED]> 4/2/01 8:50:40 AM >>> Hi Techies, I have recenty been reading Cisco Press' new book called "Peformance and Fault Management" and they stated to measure utilization on a WAN interface (full-duplex); it is recommended to use the following formula: max ( delta(ifInOctets), delta(ifOutOctets) x 8 x 100) -- (number of seconds in delta) x ifSpeed They state because of "MIB II variables are stored as counters, you must take two poll cycles and figure the difference between the two" hence the delta number. I don't understand why two poll cycles are needed and why is using "counters" attributed to this? Thanks, David _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: utilization rate calculation
You can poll it as often as you feel like. Look at it like this, we'll use a car as an example. Let's say you want to know how fast a car is going and the only tools you have available are a stopwatch and the odometer on the car. The speedometer is broken. If you only look at the odometer once and it says "100", does that tell you anything about the speed of the car? Nope. However, if you look at the odometer again after one minute and it says "102" then you know two things: 1) the car has gone two miles in one minute and hence is going 120 miles per hour, and 2) the driver should lose his license. (No offense Dave, I know you'll read this!) The same principle holds for MIB counters. The counters we're talking about increment once for each byte transmitted or received. Looking at it once doesn't help you much because you can't derive a rate from a single sample. If you have a lot of traffic perhaps one sample a minute isn't good enough for you, especially if the traffic is bursty. In a situation like that you might want to sample every 5 or 10 seconds just for fun to watch the ebb and flow of traffic on a link. >>> "Luong, David" <[EMAIL PROTECTED]> 4/2/01 10:30:05 AM >>> It makes more sense now. So it is like 2 polling cycle is MINIMUM in order to get a rate? I could use more than 2? David. -Original Message- From: John Neiberger [mailto:[EMAIL PROTECTED]] Sent: Monday, April 02, 2001 8:25 AM To: [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Subject: Re: utilization rate calculation I'll try to restate this in a way that makes sense, but the text you quoted says it pretty well. The MIB data you are accessing is stored as a counter that increments for each byte transmitted and received. Let's say you polled the router and got this information: InOctets: 543980 OutOctets: 234095 Does that tell you anything? Not really. However if you wait a minute and poll it again you could see the amount of traffic in and out of that interface over a period of time, which gives you a rate. A single poll will not give you any usefull information. To get a rate, you need to sample the data over time. In this case the data is stored in bytes so you multiply times eight to get the rate in bits per second. Does that help? If not, I'll try again later after some more coffee. John >>> "Luong, David" <[EMAIL PROTECTED]> 4/2/01 8:50:40 AM >>> Hi Techies, I have recenty been reading Cisco Press' new book called "Peformance and Fault Management" and they stated to measure utilization on a WAN interface (full-duplex); it is recommended to use the following formula: max ( delta(ifInOctets), delta(ifOutOctets) x 8 x 100) -- (number of seconds in delta) x ifSpeed They state because of "MIB II variables are stored as counters, you must take two poll cycles and figure the difference between the two" hence the delta number. I don't understand why two poll cycles are needed and why is using "counters" attributed to this? Thanks, David _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: utilization rate calculation
Thank-you John for the clear explaination. I think I got confused when the book stated "MIB II variables are stored as counters, you must take two poll cycles...". Two? why two? But now I know that is just a minimum to get a rate calculation..not a value that u MUST use. -Original Message- From: John Neiberger [mailto:[EMAIL PROTECTED]] Sent: Monday, April 02, 2001 10:17 AM To: [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Subject: RE: utilization rate calculation You can poll it as often as you feel like. Look at it like this, we'll use a car as an example. Let's say you want to know how fast a car is going and the only tools you have available are a stopwatch and the odometer on the car. The speedometer is broken. If you only look at the odometer once and it says "100", does that tell you anything about the speed of the car? Nope. However, if you look at the odometer again after one minute and it says "102" then you know two things: 1) the car has gone two miles in one minute and hence is going 120 miles per hour, and 2) the driver should lose his license. (No offense Dave, I know you'll read this!) The same principle holds for MIB counters. The counters we're talking about increment once for each byte transmitted or received. Looking at it once doesn't help you much because you can't derive a rate from a single sample. If you have a lot of traffic perhaps one sample a minute isn't good enough for you, especially if the traffic is bursty. In a situation like that you might want to sample every 5 or 10 seconds just for fun to watch the ebb and flow of traffic on a link. >>> "Luong, David" <[EMAIL PROTECTED]> 4/2/01 10:30:05 AM >>> It makes more sense now. So it is like 2 polling cycle is MINIMUM in order to get a rate? I could use more than 2? David. -Original Message- From: John Neiberger [mailto:[EMAIL PROTECTED]] Sent: Monday, April 02, 2001 8:25 AM To: [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Subject: Re: utilization rate calculation I'll try to restate this in a way that makes sense, but the text you quoted says it pretty well. The MIB data you are accessing is stored as a counter that increments for each byte transmitted and received. Let's say you polled the router and got this information: InOctets: 543980 OutOctets: 234095 Does that tell you anything? Not really. However if you wait a minute and poll it again you could see the amount of traffic in and out of that interface over a period of time, which gives you a rate. A single poll will not give you any usefull information. To get a rate, you need to sample the data over time. In this case the data is stored in bytes so you multiply times eight to get the rate in bits per second. Does that help? If not, I'll try again later after some more coffee. John >>> "Luong, David" <[EMAIL PROTECTED]> 4/2/01 8:50:40 AM >>> Hi Techies, I have recenty been reading Cisco Press' new book called "Peformance and Fault Management" and they stated to measure utilization on a WAN interface (full-duplex); it is recommended to use the following formula: max ( delta(ifInOctets), delta(ifOutOctets) x 8 x 100) -- (number of seconds in delta) x ifSpeed They state because of "MIB II variables are stored as counters, you must take two poll cycles and figure the difference between the two" hence the delta number. I don't understand why two poll cycles are needed and why is using "counters" attributed to this? Thanks, David _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: utilization rate calculation
Why do the hard work? Point MRTG at it and let it graph it all for you. Here are some examples: http://artoo.net/mrtg/ Download from: http://ee-staff.ethz.ch/~oetiker/webtools/mrtg/ -- Jason Roysdon, CCNP+Security/CCDP, MCSE, CNA, Network+, A+ List email: [EMAIL PROTECTED] Homepage: http://jason.artoo.net/ Cisco resources: http://r2cisco.artoo.net/ ""John Neiberger"" <[EMAIL PROTECTED]> wrote in message sac8456a.085@fsutil01">news:sac8456a.085@fsutil01... > I'll try to restate this in a way that makes sense, but the text you > quoted says it pretty well. The MIB data you are accessing is stored as > a counter that increments for each byte transmitted and received. Let's > say you polled the router and got this information: > > InOctets: 543980 > OutOctets: 234095 > > Does that tell you anything? Not really. However if you wait a minute > and poll it again you could see the amount of traffic in and out of that > interface over a period of time, which gives you a rate. A single poll > will not give you any usefull information. To get a rate, you need to > sample the data over time. In this case the data is stored in bytes so > you multiply times eight to get the rate in bits per second. > > Does that help? If not, I'll try again later after some more coffee. > > > John > > >>> "Luong, David" <[EMAIL PROTECTED]> 4/2/01 8:50:40 AM >>> > Hi Techies, > > I have recenty been reading Cisco Press' new book called "Peformance > and > Fault Management" and they stated to measure utilization on a WAN > interface > (full-duplex); it is recommended to use the following formula: > > max ( delta(ifInOctets), delta(ifOutOctets) x 8 x 100) > -- > (number of seconds in delta) x ifSpeed > > They state because of "MIB II variables are stored as counters, you > must > take two poll cycles and figure the difference between the two" hence > the > delta number. I don't understand why two poll cycles are needed and why > is > using "counters" attributed to this? > > Thanks, > > David _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
Re: [RE: utilization rate calculation]
Hi, Talking about MIB II etc, where can I find information on these definitions and how to use SNMP with its variables? I mean all there is to know about SNMP!! Thanks in advance Dzilo "Luong, David" <[EMAIL PROTECTED]> wrote: Thank-you John for the clear explaination. I think I got confused when the book stated "MIB II variables are stored as counters, you must take two poll cycles...". Two? why two? But now I know that is just a minimum to get a rate calculation..not a value that u MUST use. -Original Message- From: John Neiberger [mailto:[EMAIL PROTECTED]] Sent: Monday, April 02, 2001 10:17 AM To: [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Subject: RE: utilization rate calculation You can poll it as often as you feel like. Look at it like this, we'll use a car as an example. Let's say you want to know how fast a car is going and the only tools you have available are a stopwatch and the odometer on the car. The speedometer is broken. If you only look at the odometer once and it says "100", does that tell you anything about the speed of the car? Nope. However, if you look at the odometer again after one minute and it says "102" then you know two things: 1) the car has gone two miles in one minute and hence is going 120 miles per hour, and 2) the driver should lose his license. (No offense Dave, I know you'll read this!) The same principle holds for MIB counters. The counters we're talking about increment once for each byte transmitted or received. Looking at it once doesn't help you much because you can't derive a rate from a single sample. If you have a lot of traffic perhaps one sample a minute isn't good enough for you, especially if the traffic is bursty. In a situation like that you might want to sample every 5 or 10 seconds just for fun to watch the ebb and flow of traffic on a link. >>> "Luong, David" <[EMAIL PROTECTED]> 4/2/01 10:30:05 AM >>> It makes more sense now. So it is like 2 polling cycle is MINIMUM in order to get a rate? I could use more than 2? David. -Original Message- From: John Neiberger [mailto:[EMAIL PROTECTED]] Sent: Monday, April 02, 2001 8:25 AM To: [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Subject: Re: utilization rate calculation I'll try to restate this in a way that makes sense, but the text you quoted says it pretty well. The MIB data you are accessing is stored as a counter that increments for each byte transmitted and received. Let's say you polled the router and got this information: InOctets: 543980 OutOctets: 234095 Does that tell you anything? Not really. However if you wait a minute and poll it again you could see the amount of traffic in and out of that interface over a period of time, which gives you a rate. A single poll will not give you any usefull information. To get a rate, you need to sample the data over time. In this case the data is stored in bytes so you multiply times eight to get the rate in bits per second. Does that help? If not, I'll try again later after some more coffee. John >>> "Luong, David" <[EMAIL PROTECTED]> 4/2/01 8:50:40 AM >>> Hi Techies, I have recenty been reading Cisco Press' new book called "Peformance and Fault Management" and they stated to measure utilization on a WAN interface (full-duplex); it is recommended to use the following formula: max ( delta(ifInOctets), delta(ifOutOctets) x 8 x 100) -- (number of seconds in delta) x ifSpeed They state because of "MIB II variables are stored as counters, you must take two poll cycles and figure the difference between the two" hence the delta number. I don't understand why two poll cycles are needed and why is using "counters" attributed to this? Thanks, David Get free email and a permanent address at http://www.netaddress.com/?N=1 _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
RE: [RE: utilization rate calculation]
This is a good start Dzilo... http://www.cisco.com/cpress/cc/td/cpress/fund/ith2nd/it2452.htm -Original Message- From: Charles Nunie [mailto:[EMAIL PROTECTED]] Sent: Tuesday, April 03, 2001 6:13 AM To: Luong David Cc: [EMAIL PROTECTED] Subject: Re: [RE: utilization rate calculation] Hi, Talking about MIB II etc, where can I find information on these definitions and how to use SNMP with its variables? I mean all there is to know about SNMP!! Thanks in advance Dzilo "Luong, David" <[EMAIL PROTECTED]> wrote: Thank-you John for the clear explaination. I think I got confused when the book stated "MIB II variables are stored as counters, you must take two poll cycles...". Two? why two? But now I know that is just a minimum to get a rate calculation..not a value that u MUST use. -Original Message- From: John Neiberger [mailto:[EMAIL PROTECTED]] Sent: Monday, April 02, 2001 10:17 AM To: [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Subject: RE: utilization rate calculation You can poll it as often as you feel like. Look at it like this, we'll use a car as an example. Let's say you want to know how fast a car is going and the only tools you have available are a stopwatch and the odometer on the car. The speedometer is broken. If you only look at the odometer once and it says "100", does that tell you anything about the speed of the car? Nope. However, if you look at the odometer again after one minute and it says "102" then you know two things: 1) the car has gone two miles in one minute and hence is going 120 miles per hour, and 2) the driver should lose his license. (No offense Dave, I know you'll read this!) The same principle holds for MIB counters. The counters we're talking about increment once for each byte transmitted or received. Looking at it once doesn't help you much because you can't derive a rate from a single sample. If you have a lot of traffic perhaps one sample a minute isn't good enough for you, especially if the traffic is bursty. In a situation like that you might want to sample every 5 or 10 seconds just for fun to watch the ebb and flow of traffic on a link. >>> "Luong, David" <[EMAIL PROTECTED]> 4/2/01 10:30:05 AM >>> It makes more sense now. So it is like 2 polling cycle is MINIMUM in order to get a rate? I could use more than 2? David. -Original Message- From: John Neiberger [mailto:[EMAIL PROTECTED]] Sent: Monday, April 02, 2001 8:25 AM To: [EMAIL PROTECTED] Cc: [EMAIL PROTECTED] Subject: Re: utilization rate calculation I'll try to restate this in a way that makes sense, but the text you quoted says it pretty well. The MIB data you are accessing is stored as a counter that increments for each byte transmitted and received. Let's say you polled the router and got this information: InOctets: 543980 OutOctets: 234095 Does that tell you anything? Not really. However if you wait a minute and poll it again you could see the amount of traffic in and out of that interface over a period of time, which gives you a rate. A single poll will not give you any usefull information. To get a rate, you need to sample the data over time. In this case the data is stored in bytes so you multiply times eight to get the rate in bits per second. Does that help? If not, I'll try again later after some more coffee. John >>> "Luong, David" <[EMAIL PROTECTED]> 4/2/01 8:50:40 AM >>> Hi Techies, I have recenty been reading Cisco Press' new book called "Peformance and Fault Management" and they stated to measure utilization on a WAN interface (full-duplex); it is recommended to use the following formula: max ( delta(ifInOctets), delta(ifOutOctets) x 8 x 100) -- (number of seconds in delta) x ifSpeed They state because of "MIB II variables are stored as counters, you must take two poll cycles and figure the difference between the two" hence the delta number. I don't understand why two poll cycles are needed and why is using "counters" attributed to this? Thanks, David Get free email and a permanent address at http://www.netaddress.com/?N=1 _ FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
