Don't chown supervisor socket if it doesn't exist.

scripts/lib/install

@@ -66,7 +66,10 @@ ln -nsf /etc/zulip/settings.py "$deploy_path"/zproject/local_settings.py
 mkdir -p "$deploy_path"/prod-static/serve
 cp -rT "$deploy_path"/prod-static/serve /home/zulip/prod-static
 chown -R zulip:zulip /home/zulip /var/log/zulip /etc/zulip/settings.py
+if [ -e "/var/run/supervisor.sock" ]; then
+    # If supervisor isn't running, no need to chown its socket
     chown zulip:zulip /var/run/supervisor.sock
+fi
 
 cd /home/zulip/deployments/current
 

scripts/setup/postgres-init-db

@@ -3,7 +3,9 @@ set -e
 set -x
 
 # Shut down all services to ensure a quiescent state.
+if [ -e "/var/run/supervisor.sock" ]; then
     supervisorctl stop all
+fi
 
 # Drop any open connections to any old database.  Hackishly call using
 # source because postgres user can't read /root/zulip/scripts/setup.