Brief about Cisco IP SLAs and how they configure on your devices

Cisco IOS IP SLAs sends data across the network to measure performance between multiple network locations or across multiple network paths. It simulates network data and IP services and collects network performance information in real time.

 Cisco IOS IP SLAs generates and analyses traffic either between Cisco IOS devices or from a Cisco IOS device to a remote IP device such as a network application server. Cisco IP SLAs is Layer 2 transport independent, you can configure end-to-end operations over disparate networks to best reflect the metrics that an end user is likely to experience.

 Cisco IOS IP SLAs operation, various network performance statistics are monitored within the Cisco device and stored in both command-line interface (CLI) and Simple Network Management Protocol (SNMP) MIBs. 

IP SLAs packets have configurable IP and application layer options such as source and destination IP address, User Datagram Protocol (UDP)/TCP port numbers, a type of service (ToS) byte (including Differentiated Services Code Point [DSCP] and IP Prefix bits), Virtual Private Network (VPN) routing/forwarding instance (VRF), and URL web address.

Fig 1.1- IP SLAs
IP SLA collects the data based on the parameters such as Delay (both round-trip and one-way); Jitter; Packet Loss; Packet Sequencing; Path per hop; Connectivity and Website downtime.

IP SLAs to monitor the performance between any area in the network—core, distribution, and edge—without deploying a physical probe. It uses generated traffic to measure network performance between two networking devices. IP SLAs begins when the source device sends a generated packet to the destination device. 

After the destination device receives the packet, depending on the type of IP SLAs operation, it responds with time-stamp information for the source to make the calculation on performance metrics. An IP SLAs operation performs a network measurement from the source device to a destination in the network using a specific protocol such as UDP.

 Cisco IOS IP SLAs is SNMP-accessible, it can also be used by performance-monitoring applications like IPM and other third-party Cisco partner performance management products.

To implement IP SLAs network performance measurement, you need to perform these tasks:
  • Enable the IP SLAs responder, if required.
  • Configure the required IP SLAs operation type.
  • Configure any options available for the specified operation type.
  • Configure threshold conditions, if required.
  • Schedule the operation to run, then let the operation run for a period of time to gather statistics.
  • Display and interpret the results of the operation using the Cisco IOS CLI or a network management system (NMS) system with SNMP.

Configure an ICMP echo IP SLAs operation

NDNA(config)# ip sla 5
NDNA(config-ip-sla)# icmp-echo
NDNA(config-ip-sla-echo)# frequency 30
NDNA(config-ip-sla-echo)# exit
NDNA(config)# ip sla schedule 5 start-time now life forever
NDNA(config)# end

IP Address used in the above mentioned example of configuration is just for the demo purpose and has no relevance with any of the live or the enterprise network.

 Configure an IP SLA CFM Probe or Jitter Operation

NDNA(config)# ip sla 1
NDNA(config-ip-sla)# ethernet echo mpid 23 domain abc vlan 8
NDNA(config-ip-sla-ethernet-echo)# exit
NDNA(config)# ip sla schedule 1 start-time now