Database Access Details - How do you manage the information ?

I hope we all are managing small -medium - large number of databases which runs in N servers. Say , If I have 40 databases which runs in 40 + servers, How do you manage the credentials / environment details. Do you use an excel sheet which stores details like client name,hostname,RAC/Single , os user name/password , sys password,SYSASM password, application schemas & passwords, what purpose it is is used for,Standby is there / not, CDC environment,Staging,Testing etc etc. How do you manage these information. Is there a standard tool / some repository which can hold all these information so that it can be shared to the members of the DBA team ( Any Free tool ? )

Just curious to know how all manages the details of their data centre DB environments.Appreciate if you can share any template / suggestions from your experience

Cheers,
SSN

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