Custom Security List:

Its a User-defined firewall rules for better security and network control in OCI, mainly its a security list created manually by you with only the rules you need.

Real-Life Analogy

Default security list = One common lock for whole building

Custom security list = Separate locks for each room

Steps to create custom SL in OCI:

Will remove the default security list

Newly created custome list has been attahced

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N w troubleshooting ‐ Unable to Ping server

If there are two instance created within same subnet they can communicate via private ip instead the public on as they will not need internet.

In this lab will see how two instance withnin same subnet will communicate.

Conceptual view of this lab:

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Source instance:

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Destination instance:

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Step in OCI

login to the Bastioan_source_server from my laptop via putty:

As security list does not have any ingress rule for my laptop hence login fail will try to login after adding my machine IP into the SL of Bastioan_source_server.

Sucessfully login:

Try to ping google.com however its not working hence will udpate the egress rule in our custom SL.

Now will ping from Bastioan_source_server to Bastioan_Destination_Server via there private IP as both the instance is in same VCN however it will not work as private ip has not been assinged in custom SL

Unable to ping

Now will try to perform telenet from Bastioan_source_server to Bastioan_destination_server

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