Deploying SailFin in Production: Best Practices and Security Tips

Deploying SailFin in Production: Best Practices and Security TipsSailFin is an open-source SIP (Session Initiation Protocol) application server built on top of GlassFish. It provides a scalable, flexible platform for SIP-based services such as voice, video, conferencing, and presence. Deploying SailFin in production requires careful planning, secure configuration, performance tuning, and ongoing monitoring to ensure reliability and protect sensitive communications. This article walks through best practices and security tips for a production-grade SailFin deployment.

1. Architecture and Planning

Plan your SailFin deployment according to expected load, redundancy requirements, network topology, and integration points.

• Capacity planning
  • Estimate concurrent SIP sessions, call attempts per second, media throughput, and application logic processing needs.
  • Include headroom for peak traffic (recommended 20–50% buffer).
• High availability & redundancy
  • Use SailFin clusters to distribute SIP servlet instances across multiple nodes.
  • Deploy at least two nodes per cluster in separate failure domains (different racks/data centers) to avoid single points of failure.
• Network topology
  • Separate signaling and media paths if possible. Use RTP media proxies or media servers for NAT traversal and media anchoring.
  • Plan for SIP load balancers (stateless or stateful) and Session Border Controllers (SBCs) at the network edge.
• Integration
  • Identify integrations with databases, LDAP/Radius, application backends, billing systems, and third-party media servers.
  • Ensure integration points are scalable and secure.

2. Installation and Platform Considerations

• Supported platform
  • Run SailFin on a supported OS and JVM. Prefer a long-term support Linux distribution (e.g., Ubuntu LTS, RHEL/CentOS Stream) and a stable Oracle/OpenJDK build consistent across nodes.
• Resource sizing
  • Allocate CPU, memory, disk I/O, and network bandwidth according to your capacity plan. For SIP-heavy workloads, prioritize CPU and network.
• Filesystem and storage
  • Use fast, redundant storage for logs, call detail records (CDRs), and application data. Consider separate disks for OS and application data.
• Time synchronization
  • Ensure NTP or chrony is configured across nodes for consistent timestamps (important for logs, security tokens, and certificates).

3. SailFin Configuration Best Practices

• Use clustering
  • Configure SailFin clusters for session replication and failover. Test failover scenarios regularly.
• JVM tuning
  • Tune heap size, garbage collector, and JVM flags for low-latency SIP processing. Use G1GC or other modern collectors and monitor GC pause times.
  • Example JVM options to consider (adjust to your environment):

    
    -Xms8g -Xmx8g -XX:+UseG1GC -XX:MaxGCPauseMillis=200 -XX:+HeapDumpOnOutOfMemoryError 

• Thread pools and connectors
  • Adjust thread pools for SIP listeners and HTTP connectors to match expected concurrency. Avoid thread starvation.
• Persistence
  • If using persistent stores (for sessions, CDRs, or configuration), use reliable, clustered databases and ensure data replication.
• Logging
  • Configure log rotation and retention policies. Use structured logs (JSON) if integrating with centralized log systems.
• Health checks
  • Implement application-level health checks (SIP servlet responsiveness, JVM health, database connectivity) for orchestration systems.

4. Network, SIP, and Media Considerations

• NAT traversal and SIP signaling
  • Use proper SIP headers (Via, Contact) handling and consider STUN/TURN/ICE for endpoints behind NAT.
  • Configure external addresses and advertised host/port correctly in SailFin so SIP messages contain reachable contact information.
• Session Border Controllers (SBCs)
  • Place SBCs at the network edge to handle topology hiding, security, and media anchoring.
• Media servers and RTP
  • Offload media handling to dedicated media servers when mixing/transcoding is required. Ensure RTP ports are allocated and firewall rules permit media flows.
• QoS
  • Tag SIP and RTP traffic with appropriate DSCP markings and ensure network devices honor QoS policies to prioritize real-time media.

5. Security Best Practices

• Secure administrative access
  • Restrict SailFin admin consoles to management networks or VPNs. Use strong, unique admin passwords and role-based access.
  • Use key-based SSH access for servers and disable password SSH where possible.
• TLS for signaling
  • Use TLS (SIPS) for SIP signaling to encrypt call setup messages and protect credentials. Obtain certificates from trusted CAs and automate renewal (e.g., via ACME).
  • Configure strong cipher suites and disable weak protocols (e.g., TLS 1.0/1.1).
• SRTP for media
  • Use SRTP to encrypt RTP media where endpoints support it. For media anchored through media servers, ensure SRTP is negotiated end-to-end or on the media path.
• Authentication and authorization
  • Enforce strong authentication for SIP endpoints (digest or mutual TLS) and rate-limit registration attempts to prevent abuse.
  • Integrate with centralized user stores (LDAP/RADIUS) for credential management and accounting.
• Firewalling and least privilege
  • Expose only necessary SIP and RTP ports. Use firewalls and SBCs to hide internal topology and drop malformed packets.
• Rate limiting and DoS protection
  • Implement ingress filtering and rate limiting for SIP messaging to mitigate DOS attacks. Monitor for suspicious traffic patterns.
• Secure configuration storage
  • Protect configuration files and secrets (passwords, keys) using OS-level permissions or secret management systems (HashiCorp Vault, AWS Secrets Manager).
• Logging and audit
  • Log security-relevant events (failed auth, config changes, admin logins). Retain logs per compliance requirements and protect them from tampering.
• Patch management
  • Regularly apply security updates for SailFin, GlassFish components, OS, JVM, and dependencies.

6. Monitoring, Metrics, and Alerting

• Key metrics to monitor
  • Number of active SIP sessions, call setup time, call failure rates, registration counts, SIP message rates, GC pause times, CPU, memory, and network utilization.
• Use observability tools
  • Export JVM and application metrics to Prometheus, Graphite, or other monitoring systems. Visualize with Grafana and set meaningful alerts.
• Synthetic checks
  • Run synthetic SIP transactions (registrations, inbound/outbound calls) from multiple locations to detect routing or media issues.
• Call detail records (CDRs) and billing
  • Ensure CDR generation is reliable and CDRs are shipped to downstream billing/analytics systems promptly and securely.
• Incident response
  • Maintain runbooks for common failures (node crash, SIP flood, media server outage) including rollback and failover procedures.

7. Scaling and Performance Testing

• Load testing
  • Conduct realistic load tests that emulate concurrency, registration churn, and call durations. Use SIP traffic generators (sipp, SIPp, JMeter SIP plugins).
• Horizontal scaling
  • Add SailFin nodes and rebalance clusters to handle increased load. Ensure session stickiness or replication is configured appropriately for SIP dialogs.
• Microservices and service decomposition
  • Where possible, separate signaling logic, media handling, and application business logic into components that can scale independently.
• Performance tuning cycles
  • Iterate: measure, identify bottlenecks, tune, and re-measure. Focus on CPU, network I/O, thread contention, and GC behavior.

8. Backup, Recovery, and Disaster Planning

• Backups
  • Regularly back up configuration, certificates, databases, and CDRs. Test restores periodically.
• Disaster recovery
  • Maintain a documented DR plan: RTO/RPO targets, failover runbooks, and alternate datacenter readiness.
• Configuration as code
  • Keep SailFin and infrastructure configurations in version control (Git). Automate deployments with CI/CD pipelines to ensure reproducible environments.

9. Compliance and Privacy

• Data retention
  • Implement retention policies for logs and CDRs matching legal and business requirements.
• Encryption and access controls
  • Encrypt sensitive data at rest and in transit. Limit access to PII and call metadata to authorized personnel only.
• Regulatory requirements
  • Ensure recording, wiretap, and emergency call handling complies with local laws (e.g., lawful intercept where applicable).

10. Practical Checklist Before Going Live

• Validate configuration in a staging environment mirroring production.
• Confirm TLS certificates are valid and auto-renewal is set up.
• Test failover between cluster nodes and datacenters.
• Run load tests to verify capacity.
• Verify logging, monitoring, and alerting are operational.
• Harden OS and JVM, close unused ports, and apply security patches.
• Document runbooks and train on-call staff.

Deploying SailFin in production successfully is a mix of careful planning, secure defaults, performance tuning, and robust operational practices. Prioritize encryption for both signaling and media, harden administrative access, automate monitoring and backups, and validate failover mechanisms before traffic is routed to the cluster. With these controls in place, SailFin can provide a resilient platform for SIP-based services at scale.