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New Member

Hardware Requirement for IP SLA Shadow Router

Hi All,

I would like to implement an IP SLA shadow router running pathEcho application with 365 IP SLA instances. I tried it on a Cisco2811 with 64MB flash and 256MB memory. The problem is that the Cisco2811 cannot handle all the operation when put into production. The router cannot be access/managed anymore. Any suggestion will be much appreciated on what platform I can use to support all the IP SLA instances that I would like to run.

Many Thanks,

Almar

1 ACCEPTED SOLUTION

Accepted Solutions

Re: Hardware Requirement for IP SLA Shadow Router

Hello,

How are you starting these 365 IP SLA sessions? Simultaneous or sequentially?

Q. What is a dedicated (shadow) SLAs router?  What are the benefits?

A. The dedicated or SLAs router is used exclusively for Cisco IOS IP SLAs  operations and is connected to the edge routers to simulate the customer  network traffic. It is typically a Cisco 2600, 2800, 3700, 3800, or  7200 Series Router.

So, your device is recommended by Cisco to be use as dedicated SLA router.

Regarding the CPU and memory utilisation:
Q. To what extent does Cisco IOS IP SLAs  impact CPU utilization or memory?
A. As Cisco IOS IP SLAs is a software-based measurement, it does consume  CPU usage and memory.
Table 2  illustrates the CPU usage based on 2,000 active operations, activated  sequentially. The data generated per operation is 10 packets of 64 byte  sizing, with 20ms spacing using the IP SLAs jitter operation. The data  represents four destinations, activated per one second versus percentage  of CPU usage in a 12.4 Cisco IOS release.

Table 2. Cisco IOS IP SLAs CPU Usage

Operations/ Second

Operations/ Minute

2620XM

3725

7200VXR

NPE-G1

4
240
7
2
0
The memory  used per Cisco IOS IP SLAs operation does vary with different Cisco IOS  Software releases.

Table  3. Cisco IOS IP SLAs Memory Usage

Cisco IOS Software 12.2 and above

UDP Jitter

< 12KB

UDP Echo

< 3.5KB

ICMP Echo

< 3.2 KB

More you can find here:

http://www.cisco.com/en/US/technologies/tk648/tk362/tk920/technologies_qas0900aecd8017bd5a_ps6602_Products_Q_and_A_Item.html

Your router resources should support your 365 IP SLA connections. Even if you start them simultaneously and admit that these are consuming all router resources, you will have your connection to the router stuck for some seconds and then you shoul gain the connectivity again. Check with:

show proc cpu history

show proc memory sorted

If you have spikes of utilisation or permanent memory and CPU are used to the limit.

More than this, it would help if you can paste here an excerpt about your IP SLA session configuration.

Good luck!

Calin

2 REPLIES

Re: Hardware Requirement for IP SLA Shadow Router

Hello,

How are you starting these 365 IP SLA sessions? Simultaneous or sequentially?

Q. What is a dedicated (shadow) SLAs router?  What are the benefits?

A. The dedicated or SLAs router is used exclusively for Cisco IOS IP SLAs  operations and is connected to the edge routers to simulate the customer  network traffic. It is typically a Cisco 2600, 2800, 3700, 3800, or  7200 Series Router.

So, your device is recommended by Cisco to be use as dedicated SLA router.

Regarding the CPU and memory utilisation:
Q. To what extent does Cisco IOS IP SLAs  impact CPU utilization or memory?
A. As Cisco IOS IP SLAs is a software-based measurement, it does consume  CPU usage and memory.
Table 2  illustrates the CPU usage based on 2,000 active operations, activated  sequentially. The data generated per operation is 10 packets of 64 byte  sizing, with 20ms spacing using the IP SLAs jitter operation. The data  represents four destinations, activated per one second versus percentage  of CPU usage in a 12.4 Cisco IOS release.

Table 2. Cisco IOS IP SLAs CPU Usage

Operations/ Second

Operations/ Minute

2620XM

3725

7200VXR

NPE-G1

4
240
7
2
0
The memory  used per Cisco IOS IP SLAs operation does vary with different Cisco IOS  Software releases.

Table  3. Cisco IOS IP SLAs Memory Usage

Cisco IOS Software 12.2 and above

UDP Jitter

< 12KB

UDP Echo

< 3.5KB

ICMP Echo

< 3.2 KB

More you can find here:

http://www.cisco.com/en/US/technologies/tk648/tk362/tk920/technologies_qas0900aecd8017bd5a_ps6602_Products_Q_and_A_Item.html

Your router resources should support your 365 IP SLA connections. Even if you start them simultaneously and admit that these are consuming all router resources, you will have your connection to the router stuck for some seconds and then you shoul gain the connectivity again. Check with:

show proc cpu history

show proc memory sorted

If you have spikes of utilisation or permanent memory and CPU are used to the limit.

More than this, it would help if you can paste here an excerpt about your IP SLA session configuration.

Good luck!

Calin

New Member

Re: Hardware Requirement for IP SLA Shadow Router

Hi Callin,

Thanks for your reply. Probably I will be using a Cisco 7200VXR.

Regards,

Almar

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