Deploy and Host Microsoft SQL Server 2022 on Railway

Pinned SQL Server 2022 CU26 Developer edition. Persistent data at /var/opt/mssql, public TCP 1433, and a generated sa password that meets SQL Server complexity rules.

This listing replaces rotting marketplace clones that still ship mcr.microsoft.com/mssql/server:2022-latest (or a GitHub Dockerfile ARG TAG_NAME=2022-latest) with no CU pin.

About Hosting Microsoft SQL Server 2022 on Railway

Railway pulls the official Microsoft image mcr.microsoft.com/mssql/server:2022-CU26-ubuntu-22.04 (not :latest). A volume is mounted at /var/opt/mssql so databases survive redeploys. A TCP proxy on application port 1433 exposes SSMS / Azure Data Studio / sqlcmd access. Private networking is used for other services in the same project.

The start command is /opt/mssql/bin/sqlservr -T1800. Trace flag 1800 is required on Railway volumes (4K sectors); without it SQL Server can stack-overflow after misaligned IO on master.mdf.

SQL Server on Linux wants about 2 GB RAM. MSSQL_MEMORY_LIMIT_MB=2048 caps the engine so it does not size itself against the host.

Developer edition includes Enterprise features and is licensed for development and test only, not production. ACCEPT_EULA=Y means you agree to Microsoft’s SQL Server EULA.

First boot can take 1–2 minutes. Wait for SQL Server is ready for client connections in the deploy logs.

Common Use Cases

App backends that speak TDS (Node mssql, .NET, JDBC, Go, Python) against a private MSSQL_URL
Local SSMS / Azure Data Studio connected through the public TCP proxy
Dev and CI databases that need a current 2022 CU instead of an unpinned :latest tag
Lift-and-shift prototypes that already assume SQL Server, not Postgres/MySQL/Redis

Dependencies for Microsoft SQL Server 2022 Hosting

Image: mcr.microsoft.com/mssql/server:2022-CU26-ubuntu-22.04
Edition: Developer (MSSQL_PID=Developer)
Volume: /var/opt/mssql
Port: 1433 (private + public TCP proxy)
Start command: /opt/mssql/bin/sqlservr -T1800
EULA: SQL Server container EULA

Deployment Dependencies

Generated (do not set on deploy)

Variable	What it is
`MSSQL_SA_PASSWORD`	`sa` password. Generated as `Aa1!${{secret(32, "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789")}}` so it always meets SQL Server complexity (upper, lower, digit, symbol, 8+ chars) without `@`/`:` breaking connection URLs.

Required / fixed

Variable	Default	Notes
`ACCEPT_EULA`	`Y`	Required. Confirms the Microsoft EULA.
`MSSQL_PID`	`Developer`	Edition or product key.
`MSSQL_USERNAME`	`sa`	Built-in sysadmin. Cannot be renamed.
`MSSQL_TCP_PORT`	`1433`	Private listen port.
`MSSQL_MEMORY_LIMIT_MB`	`2048`	Caps SQL Server memory.
`RAILWAY_RUN_UID`	`0`	Lets the volume at `/var/opt/mssql` be writable.
`RAILWAY_SHM_SIZE_BYTES`	`268435456`	256 MB `/dev/shm`.

Private and public hosts

Other Railway services should use the private URL. SSMS / Azure Data Studio / local tools use the public TCP proxy.

Variable	Value	Use
`MSSQL_SERVER`	`${{RAILWAY_PRIVATE_DOMAIN}}`	Private hostname
`MSSQL_TCP_PORT`	`1433`	Private port
`MSSQL_SERVER_PUBLIC`	`${{RAILWAY_TCP_PROXY_DOMAIN}}`	Public TCP proxy hostname
`MSSQL_TCP_PORT_PUBLIC`	`${{RAILWAY_TCP_PROXY_PORT}}`	Public TCP proxy port
`MSSQL_URL`	`sqlserver://${{MSSQL_USERNAME}}:${{MSSQL_SA_PASSWORD}}@${{MSSQL_SERVER}}:${{MSSQL_TCP_PORT}}`	Private connection URL
`MSSQL_URL_PUBLIC`	`sqlserver://${{MSSQL_USERNAME}}:${{MSSQL_SA_PASSWORD}}@${{MSSQL_SERVER_PUBLIC}}:${{MSSQL_TCP_PORT_PUBLIC}}`	Public connection URL

From another service in the same project:

${{MicrosoftSQL.MSSQL_URL}}

Drivers that need Encrypt (ADO.NET, recent mssql Node, JDBC):

Server=${{MicrosoftSQL.MSSQL_SERVER}},1433;User Id=sa;Password=${{MicrosoftSQL.MSSQL_SA_PASSWORD}};Encrypt=True;TrustServerCertificate=True

Public / off-Railway clients use MSSQL_SERVER_PUBLIC and MSSQL_TCP_PORT_PUBLIC instead.

How to log in

Open the MicrosoftSQL service → Variables
Copy MSSQL_SA_PASSWORD
Private (same Railway project): host MSSQL_SERVER, port 1433, user sa
Public (SSMS, Azure Data Studio, local app): host MSSQL_SERVER_PUBLIC, port MSSQL_TCP_PORT_PUBLIC, user sa
Enable encrypt + trust server certificate if the client requires TLS

sqlcmd example (public proxy):

sqlcmd -S "$MSSQL_SERVER_PUBLIC,$MSSQL_TCP_PORT_PUBLIC" -U sa -P "$MSSQL_SA_PASSWORD" -C -Q "SELECT @@VERSION"

Why Deploy Microsoft SQL Server 2022 on Railway

Railway handles the image pull, volume, private DNS, and TCP proxy. This template is healthier than rotting marketplace clones because it:

Pins a CU tag (2022-CU26-ubuntu-22.04), not :latest / 2022-latest
Mounts a volume at /var/opt/mssql so data survives deploys
Starts with trace flag 1800 so Railway 4K volumes do not stack-overflow on misaligned IO
Generates an SA secret that satisfies SQL Server password complexity
Exposes TCP 1433 and documents private + public host/URL variables
Sets Developer edition + EULA explicitly (MSSQL_PID, ACCEPT_EULA=Y)
Caps memory with MSSQL_MEMORY_LIMIT_MB=2048

Official Railway Postgres / MySQL / Redis templates are already healthy. This listing is MSSQL only.

By setting ACCEPT_EULA=Y you accept the SQL Server container EULA. Developer edition is not licensed for production.