How Slow DNS Puts Valkey Sentinel Into TILT
A team running BetterDB reported a Valkey Sentinel deployment that kept logging +tilt and flagging +sdown on healthy nodes, with raw IPs and plaintext as the only known workaround. This is the reproduction and the isolation matrix: a blocking getaddrinfo on Sentinel's single-threaded loop is the cause, TLS is not, and an FQDN in announce-ip stalls the peer Sentinels rather than the one that announced it. Verified on Valkey 8.1.8 and 9.0.6.
Kristiyan Ivanov•