Hey there! We've found the following might help you get unblocked faster:

• 🧵 TCP Proxy for PostgreSQL not accepting connections - Connection timeout
• 🧵 Railway Support Ticket: Private Networking Not Resolving
• 🧵 MongoDB Connection Issue: Client Disconnects Immediately After Successful Authentication

If you find the answer from one of these, please let us know by solving the thread!

AI-assisted; checked against current Railway and Apache Cassandra docs. I have not tested your instance.

Railway’s TCP proxy carries raw TCP; do not assume the automatic HTTPS certificates for web domains apply to Cassandra. Match the TLS/auth settings used by your working scylla connection.

First compare the exact host AND port. The proxy’s internal target should be Cassandra’s native transport listener (usually 9042), but an external cqlsh client must use Railway’s generated PUBLIC proxy port, not automatically 9042:

cqlsh PROXY_HOST PUBLIC_PROXY_PORT -u USERNAME --debug

Use the hostname without a scheme or :port suffix; the port is the separate argument. Do not put the password in the command or post it here.

If Cassandra requires client TLS, add --ssl and configure the trusted CA/certificate settings in cqlshrc. Keep certificate verification enabled. If a certificate error appears, check trust and hostname compatibility rather than disabling verification.

Also use the cqlsh shipped with your server’s Cassandra release: Apache only guarantees that pairing, whereas another driver can negotiate differently.

If this still fails, please share the exception category/message with credentials removed, cqlsh version, server version, and whether scylla uses the same public endpoint and TLS. Those distinguish connection timeout/refusal, authentication, TLS and protocol problems.

References:

https://docs.railway.com/networking/tcp-proxy

https://cassandra.apache.org/doc/latest/cassandra/managing/tools/cqlsh.html