Root cause Analysis at Each layer of OSI

 

OSI LayerExample RCA Activity
Physical (Layer 1)Check damaged cables, power, or signal issues.
Data Link (Layer 2)Investigate MAC address problems, VLAN misconfigurations, or switch port issues.
Network (Layer 3)Check IP addressing, routing, subnetting, or ICMP connectivity.
Transport (Layer 4)Analyze TCP/UDP issues such as retransmissions, packet loss, or port availability.
Session (Layer 5)Investigate session establishment or maintenance problems.
Presentation (Layer 6)Check encryption, compression, or data format issues.
Application (Layer 7)Analyze application logs, HTTP errors, DNS, APIs, or database connectivity.

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