The relationship of CIR and CBS on S series switches


When configure speed limit on S series switches (except S1700), the relationship between CIR and CBS is as follows:
- CBS is greater than the maximum length of the message.
- In the case of continuous flow, there is no special requirement for CBS, and the average rate is cir.
- In the case of bursty traffic needs to be guaranteed, if the CBS is converted to kbit and less than CIR, then the CBS can not guarantee the burst traffic. Otherwise CBS can be configured larger.
If you want to limit the FTP service, as FTP belongs to the TCP service, the TCP protocol has its special transmission mechanism, which leads to the failure of the speed limit, the recommended configuration:
- CBS = 200 * CIR
- PBS = 2 * CBS
- don't configure PIR, only confire CIR, CBS, PBS.
CIR unit is kbit/s, CBS, PBS unit is byte.
For example: configure CIR bandwidth to 2Mbit/s = 2048kbit/s, then:
CBS = 200 * CIR = 200 * 2048 = 409600
PBS = 2 * CBS = 2 * 409600 = 819200
Configuration is as follows:
[HUAWEI]traffic behavior b1
[HUAWEI-behavior-b1] car cir 2048 pir 2048 cbs 409600 pbs 8192000
[HUAWEI-behavior-b1] quit

Other related questions:
A traffic policy contains multiple pairs of traffic classifiers and behaviors. How to handle the problem if the GTS CIR command is executed in these pairs and the CIR configured is greater than the CIR configured on the interfaces
If a traffic policy includes multiple pairs of traffic classifiers and behaviors and the GTS CIR command is configured in these pairs. If the CIR of these pairs is greater than that configured on the interface, rate limiting will be configured for the pairs and interfaces.

Can an OSPF neighbor relationship be established if the network types of the two S series switches are different
Question: Can a Full neighbor relationship be established if the network types of the two ends of an OSPF link are different? Answer: Yes. For example, two devices are interconnected through an Ethernet link. On one end of the link, the default broadcast network type is adopted. The other end is configured as OSPF peer-to-peer (P2P). Neighbor relationship can be established between these two devices, which reach the Full state by exchanging their Link State Databases (LSDBs). However, no route can be learned because OSPF devices need LSDBs to construct a Shortest Path Tree (SPT). The LSDBs, however, are problematic. That is, the link-state advertisements (LSAs) generated by one end consider the peer a broadcast neighbor, while the other end considers its peer a P2P neighbor. Therefore, no SPT can be constructed correctly and the Shortest Path First (SPF) algorithm cannot calculate the right routes either.

Prevent an S series switch from setting up an OSPF neighbor relationship with a device connecting to an interface on the switch
Run the silent-interface command on an interface of an S series switch supporting OSPF. Then the switch cannot set up an OSPF relationship with the device connecting to the interface. To enable OSPF on many interfaces while disabling OSPF neighbor relationship establishment on most interfaces, run the silent-interface all command and then run the undo silent-interface command to enable OSPF neighbor relationship establishment on specified interfaces.

Unit of rate limits for S series switches
The unit of rate limits for S series switches (except S1700 switches) is kbit/s.

S series switch SNMP OID
A Management Information Base (MIB) is a database that stores the variables (information that can be queried and set by the agent) on managed devices A MIB defines the attributes of managed devices, including name, status, access permission, and data type. MIB stores information using a tree structure. The leaf nodes of the tree are managed objects (MOs). An MO is identified by the set of nodes along the path from the root to the leaf node. Such a path is called object identifier (OID). An OID consists of positive integers and zero, and it is used to uniquely identify an MO in the MIB. For example, an SNMP object can be identified as { iso(1).org(3).dod(6).internet(1).snmpV2(6) }, which can be simplified to The identifier is called an OID.

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