On Mon, Aug 17, 2026 at 07:21:49PM +0200, Erwan David via Postfix-users wrote:
> postfix/tlsmgr[8777]: warning: /var/lib/postfix/smtp_scache: hash/btree > support is deprecated. Please switch to cdb or lmdb. Caches are mutable, but the "c" in "cdb" is for "constant", a "cdb" table cannot be updated, it can only be replaced. So you need a mutable table type for the session cache. That'd be "hash", "btree", "lmdb", ... > Following https://www.postfix.org/TLS_README.html I commented out the > configuration, and it works, thus no problem, but I am curious of what I > missed Without an SMTP session cache your SMTP client will do a full TLS handshake on every new connection. If there are destinations to which you deliver a steady volume of mail, this may raise CPU cost and/or latency. "Security" maximalists will however applaud you for removing a key recovery attack vector (via a compromised session cache). FWIW, my own very low volume SMTP client nevertheless has an SMTP session cache, if my machine is compromised to reveal the cache contents, the attacker is better off walking away with tens of gigabytes of stored mail... -- Viktor. 🇺🇦 Слава Україні! _______________________________________________ Postfix-users mailing list -- [email protected] To unsubscribe send an email to [email protected]
