Re: Using PostgreSQL for NSS databases

On Thu, 2012-11-01 at 14:28 -0400, Daniel Popowich wrote:
> I'm making this post here in hopes I may save someone from beating
> their head against the wall like I did...
> I am writing a custom Name Service Switch (NSS) module to take
> advantage of already existing account information in a pg database.
> Under certain circumstances, processes will hang due to non-recursive
> mutex locking during PG connection creation.  It goes something like
> this:
> ========================================
> /etc/nsswitch.conf:
>   passwd:      files mypgmod
>   group:      files mypgmod
> ========================================

As an old sys-admin who has been using LDAP NSS for decades I'd
recommend you look at the design of the newer nss_ldapd /sssd scheme
[vs. the old nss_ldap scheme].  This runs a simple daemon that servers
the responses to NSS over a local socket and manages a small pool of
connections back to the DSA [or in your case the PostgreSQL server].
This really improves performance, both for the client and the server as
well as avoiding many concurrency issues and intermittent network
issues.

nscd has numerous problems of its own.