Firstly, the su problem was because I was still in my home directory. When I sudo su - Postgres (note the minus) all is OK.
In my travels I discovered dscl, which I had managed not to encounter over many long year. How very handy it is. I deleted the postgres user with ddcl, and then re-installed postgresql13 and server. One thing that causes confusion is that the _postgres user in /etc/passwd has a different UID and GID from the dscl user and group. It’s the same on Mojave. I have no idea what these /etc/passwd entries are about, given the underlying differences. Peter — Peter West peter.b.w...@ehealth.id.au “A prophet is not without honor, except in his hometown and among his relatives and in his own household.” > On 4 Feb 2021, at 11:45 am, Ryan Schmidt <ryandes...@macports.org> wrote: > > > > On Feb 3, 2021, at 09:04, Peter West wrote: > >> MacOS Big Sur 11.2 MacBook Air M1 >> >> I’m migrating to the M1 from an Intel MacBook Pro running Mojave. >> >> I installed postgresql13 and -server, and copied my defaultdb across from >> the Pro. >> >> I can’t vouch for the order of these things, because I wasn’t expecting to >> get into a quagmire. >> >> I tried to give the postgres user a password using passwd as root. That’s >> not enough. I have to use a command ’security’ with a reference to a >> Keychain to complete the process. In the wake of all this, I assume that the >> user postgres is created without a password, and that’s Ok with the default >> pg_hba.conf. > > As far as I know, anytime MacPorts creates a macOS user account on behalf of > a portfile that requests it, it does so without a password, and this is not > thought to be a problem. The user accounts do not have a shell set so nobody > could log into them. > > >> Then I thought that maybe I should build up the databases by dumping >> databases from the Pro and restoring to the M1. So I uninstalled the >> postgresql ports and tried to delete /opt/local/var/db/postgresql13. The >> defaultdb disappeared but root was not allowed to remove a directory Library >> sitting beside the defaultdb. It had Preferences and Keychains subdirs, and >> they wouldn’t go. > > I am not certain why. I do not have much experience with macOS 11 yet. > > >> I deleted the postgres user through the System Preferences, but that left >> the entry for _postgres in /etc/passwd. > > The fact that the postgres user was visible in System Preferences indicates a > problem. macOS user accounts that MacPorts creates for you are not visible in > System Preferences. > > You said you migrated from another Mac. In my experience, the migration > assistant will migrate any MacPorts-created user accounts improperly. After > migration, the accounts will appear in System Preferences, and their home > directories will have been moved into /Users, which may make the ports that > use those user accounts not work correctly. Cleaning up the user migration > mess that the migration assistant leaves behind is not easy. Whenever I > migrate, I choose not to migrate MacPorts-created user accounts and instead > have MacPorts recreate them properly. > > I believe the entry for _postgres in /etc/passwd is fine and normal on any > macOS system. Apple puts it there, along with creating the _postgres macOS > user account. This is unrelated to the postgres macOS user account the > MacPorts postgresql-server ports create. > > >> Ok, install postgresql13 again. Installation proceeded, but this time did >> not create the postgres user visible through System Preferences, which I >> assume was created when I first installed. > > You can check on the command line whether the postgres user created by > MacPorts exists: > > id postgres > > If that doesn't show "no such user", you're fine. > > >> When I try to access the macports wrapper (via su) to start the database, I >> get the complaint >> shell-init: error retrieving current directory: getcwd: cannot access parent >> directories: Permission denied >> could not identify current directory: Permission denied (3times) >> The program “postgres” is needed by pg_ctl but was not found in the same >> directory as pg_ctl >> (for obvious reasons, me) >> Check your installation. >> (you don’t say) > > Not sure, but try cd'ing to a different directory before doing what you did. > Maybe you were in a directory that no longer existed. MacPorts has a similar > error message that can appear if you are in a port's directory when you run > `sudo port sync` because (if you sync with rsync) that deletes all port > directories and recreates them. >
