etc/postfix/sasl_passwd is unavailable

[mastensg]

after setting up postfix on a new host, riemann, i had to follow this advice for email transmission to work:

https://serverfault.com/questions/240767/postmap-fatal-open-database-etc-postfix-sasl-passwd-db-permission-denied

errors before:

mastensg@riemann:~$ sudo tailf /var/log/mail.log 
Feb 14 09:14:50 riemann postfix/qmgr[704]: C426EA2E57: from=<[email protected]>, size=783, nrcpt=1 (queue active)
Feb 14 09:14:50 riemann postfix/smtp[2861]: warning: hash:/etc/postfix/sasl_passwd is unavailable. open database /etc/postfix/sasl_passwd.db: No such file or directory
Feb 14 09:14:50 riemann postfix/smtp[2861]: warning: hash:/etc/postfix/sasl_passwd lookup error for "smtp.sendgrid.net"
Feb 14 09:14:50 riemann postfix/smtp[2861]: warning: C426EA2E57: smtp_sasl_password_maps lookup error
Feb 14 09:14:50 riemann postfix/smtp[2861]: C426EA2E57: local data error while talking to smtp.sendgrid.net[159.122.219.55]
Feb 14 09:14:51 riemann postfix/smtp[2861]: warning: hash:/etc/postfix/sasl_passwd is unavailable. open database /etc/postfix/sasl_passwd.db: No such file or directory
Feb 14 09:14:51 riemann postfix/smtp[2861]: warning: hash:/etc/postfix/sasl_passwd lookup error for "smtp.sendgrid.net"
Feb 14 09:14:51 riemann postfix/smtp[2861]: warning: C426EA2E57: smtp_sasl_password_maps lookup error
Feb 14 09:14:51 riemann postfix/smtp[2861]: C426EA2E57: to=<[email protected]>, relay=smtp.sendgrid.net[159.122.219.43]:587, delay=0.31, delays=0.01/0/0.3/0, dsn=4.3.0, status=deferred (local data error while talking to smtp.sendgrid.net[159.122.219.43])
Feb 14 09:17:32 riemann postfix/postmap[3703]: fatal: open sasl_passwd: No such file or directory