SBC SWe: High Availability in the Cloud

SBC SWe and Virtualization: Ensuring High Availability in a Cloud Environment

In modern telecommunications networks, where uninterrupted communication is critical, high availability (HA) is a key requirement for infrastructure components. Ribbon Communications offers the Session Border Controller Software Edition (SBC SWe) solution, designed for virtualized and cloud environments. This article focuses on the architectural solutions and configuration features of SBC SWe to achieve the highest possible fault tolerance in various scenarios.

High Availability Architecture of SBC SWe

SBC SWe utilizes a redundant architecture to ensure HA. The main components of the HA architecture include:

• Active/Standby Mode: Two instances of SBC SWe operate in parallel. The active instance processes traffic, while the standby instance is in standby mode, ready to take control immediately in case of active instance failure. This approach, based on the Active/Standby principle, ensures quick failover in case of failures.
• Monitoring Mechanism: Constant monitoring of the active SBC SWe’s status to detect failures. Effective monitoring is critical for quickly detecting problems and initiating the failover procedure.
• Automatic Failover: In the event of a failure detection, automatic traffic failover to the standby SBC SWe occurs. The failover time should be minimal to avoid service interruption.
• Shared Storage: Shared configuration and session data are stored in shared storage, accessible to both SBC SWe instances. This ensures service continuity during failover. Shared storage eliminates the need for complex configuration synchronization between instances.

Benefits of HA Architecture:

• Minimal downtime in case of failure.
• Automatic service recovery.
• Transparent failover for end users.
• Simplified management and maintenance.

Implementing HA in Various Cloud Environments

SBC SWe can be deployed in various cloud environments, including private, public, and hybrid clouds. Each scenario has its own HA implementation specifics. The choice of cloud environment affects the available tools and approaches to ensuring HA.

HA in a Private Cloud (VMware, OpenStack)

In a private cloud, HA for SBC SWe can be implemented using built-in virtualization mechanisms, such as VMware HA or OpenStack Auto Scaling. These mechanisms provide automatic detection of virtual machine failures and their restart on another host. Using built-in virtualization tools simplifies HA configuration and management.

VMware HA Configuration:

1. Ensure that VMware HA is enabled in the cluster where the SBC SWe virtual machines are deployed. VMware HA is a basic component for ensuring the fault tolerance of virtual machines.
2. Configure VMware HA rules to automatically restart SBC SWe virtual machines in case of host failure. The rules define how VMware HA responds to various types of failures.
3. Use anti-affinity rules to ensure that the Active and Standby SBCs are located on different physical hosts. This prevents simultaneous failure of both SBC SWe instances in case of host failure.
4. Test the failover by simulating a host or virtual machine failure. Regular testing ensures HA operability.

Recommendation: Configure a heartbeat network between SBC SWe virtual machines to quickly detect connection failures.

OpenStack Auto Scaling Configuration:

1. Create an Auto Scaling Group for SBC SWe instances. An Auto Scaling Group provides automatic scaling and recovery of instances.
2. Configure scaling policies based on monitoring metrics (e.g., CPU utilization, memory usage). The policies define when to add or remove instances.
3. Enable health checks for instances to automatically detect failures. Health Checks allow the Auto Scaling Group to detect non-working instances.
4. Test the failover by simulating an instance failure. You need to verify that the Auto Scaling Group correctly handles failures.

Recommendation: Use OpenStack Heat to automate the deployment and configuration of the Auto Scaling Group.

HA in a Public Cloud (AWS, Azure, Google Cloud)

In a public cloud, HA for SBC SWe can be implemented using services provided by cloud providers, such as AWS Auto Scaling, Azure Availability Sets, or Google Compute Engine Managed Instance Groups. These services offer scalability and fault tolerance “out of the box”.

AWS Auto Scaling Configuration:

1. Create an Auto Scaling Group for SBC SWe instances. An Auto Scaling Group manages the lifecycle of SBC SWe instances.
2. Configure scaling policies based on Amazon CloudWatch metrics. CloudWatch provides monitoring of instance performance and status.
3. Use Elastic Load Balancer (ELB) to distribute traffic between SBC SWe instances. ELB provides load distribution and automatic failure detection.
4. Configure health checks in ELB for automatic failure detection. Health Checks allow ELB to detect non-working instances and redirect traffic to healthy ones.
5. Place instances in different Availability Zones for geographic redundancy. Placement in different Availability Zones protects against failures in one zone..

Recommendation: Use AWS CloudFormation to automate the deployment and configuration of AWS Auto Scaling.

Azure Availability Sets Configuration:

1. Create an Availability Set for SBC SWe virtual machines. An Availability Set ensures that virtual machines will be placed on different physical servers and fault domains.
2. Place virtual machines in the Availability Set to protect against hardware and maintenance failures. An Availability Set protects against planned and unplanned downtime.
3. Use Azure Load Balancer to distribute traffic between virtual machines. Azure Load Balancer distributes incoming traffic between SBC SWe instances.
4. Configure health checks in Load Balancer for automatic failure detection. Health checks allow Load Balancer to detect non-working instances and redirect traffic.

Recommendation: Use Azure Resource Manager (ARM) templates to automate the deployment and configuration of Azure Availability Sets.

Google Compute Engine Managed Instance Groups Configuration:

1. Create a Managed Instance Group for SBC SWe instances. A Managed Instance Group manages a group of identical virtual machines.
2. Configure automatic recovery and scaling policies. The policies define how the Managed Instance Group responds to failures and changes in load.
3. Use Google Cloud Load Balancing to distribute traffic between instances. Google Cloud Load Balancing provides traffic distribution and automatic failure detection.
4. Configure health checks in Load Balancing for automatic failure detection. Health checks allow Load Balancing to detect non-working instances and redirect traffic.
5. Place instances in different zones for geographic redundancy. Placement in different zones reduces the risk of service loss due to failures in one zone.

Recommendation: Use Google Cloud Deployment Manager to automate the deployment and configuration of Google Compute Engine Managed Instance Groups.

HA in a Hybrid Cloud

In a hybrid cloud, HA for SBC SWe can be implemented using a combination of approaches used in private and public clouds. It is important to ensure connectivity between private and public clouds using VPN or dedicated communication channels. Reliable communication between clouds is a key factor for ensuring HA in a hybrid environment.

Shared Storage Configuration

Shared storage is a critical component of the SBC SWe HA architecture. It must ensure data availability and consistency for both SBC SWe instances. The choice of shared storage solution directly affects HA performance and reliability.

Shared Storage Options:

• Network File System (NFS): A traditional solution for shared storage. Suitable for small and medium deployments.
• Server Message Block (SMB): A file sharing protocol used in Windows networks. An alternative to NFS, especially in Windows environments.
• iSCSI: A protocol for accessing block storage devices over an IP network. Provides higher performance than NFS and SMB.
• Object Storage (AWS S3, Azure Blob Storage, Google Cloud Storage): A solution for storing unstructured data in the cloud. Suitable for storing large volumes of data, such as call recordings.
• Clustered File Systems (GlusterFS, Ceph): Distributed file systems that provide high availability and scalability. Suitable for large and demanding deployments.

Recommendations for Shared Storage Configuration:

• Choose a solution that meets performance, availability, and scalability requirements. Consider current and future needs.
• Ensure storage redundancy and protection against data loss. Use RAID, replication, or other mechanisms to protect data.
• Configure access rights to ensure security. Restrict access to storage to only the necessary components.
• Perform regular data backups. Regular backups allow you to recover data in case of serious failures.

Important: Optimize network performance between SBC SWe and shared storage to minimize latency.

Monitoring and Management of HA

To ensure the effective operation of the SBC SWe HA architecture, it is necessary to configure a monitoring and management system that will allow you to quickly identify and resolve problems. Effective monitoring is key to maintaining high availability.

Monitoring Tools:

• Simple Network Management Protocol (SNMP): A standard protocol for monitoring network devices. Suitable for basic monitoring.
• Syslog: A protocol for collecting system logs. Allows you to analyze events and identify problems.
• REST API: An interface for programmatic access to monitoring data. Allows you to integrate SBC SWe with other monitoring systems.
• Ribbon EMS (Element Management System): A centralized management and monitoring system for Ribbon Communications products. The preferred solution for managing Ribbon products.

Monitoring Metrics:

• CPU load.
• Memory usage.
• Network load.
• Number of active sessions.
• Call processing latency.
• HA status (active/standby).
• Shared storage status.

Recommendation: Configure alerts for critical metrics to respond quickly to problems.

HA Management:

• Automatic Failover.
• Manual Switchover.
• Recovery after failure.
• Software Upgrade.
• Backup and Restore of configuration.

Important: Develop clear procedures for managing HA and train personnel.

HA Testing

Regular HA testing is a prerequisite for ensuring the reliable operation of SBC SWe. Testing should include simulating various failure scenarios, such as:

• Virtual machine failure.
• Host failure.
• Network failure.
• Shared storage failure.
• Software failure.

Testing should be conducted in a controlled environment as close as possible to the production environment. It is important to document the test results and use them to improve the HA architecture. Documenting the results allows you to identify weaknesses and improve HA procedures.

SBC SWe Configuration Features for HA

Configuring SBC SWe for High Availability requires special attention to the following aspects:

Configuration Synchronization:

The configuration of the active and standby SBC SWe must be identical. Using shared storage to store the configuration is the recommended approach. Automate the configuration synchronization process to avoid errors.

Session Data Synchronization:

To ensure service continuity during failover, it is necessary to synchronize session data between the active and standby SBC SWe. This can be implemented using a session replication mechanism. The choice of session replication method depends on performance and availability requirements.

Keepalive Configuration:

The Keepalive mechanism is used to monitor the status of the active SBC SWe. It is important to properly configure Keepalive parameters to ensure timely detection of failures. Too short a Keepalive interval can lead to false positives, and too long an interval can lead to late failure detection.

Priority Setting:

The active SBC SWe should be assigned a higher priority than the standby one to ensure its selection as active after rebooting. Correct priority setting is important for automatic recovery after a failure.

Routing Configuration:

Traffic routing should be configured so that traffic is routed to the active SBC SWe. This can be implemented using DNS, Load Balancer, or other mechanisms. The choice of routing mechanism depends on the network architecture and performance requirements.

Recommendations for Ensuring High Availability

In conclusion, here are some recommendations for ensuring high availability for SBC SWe in a cloud environment:

• Use a redundant architecture with active and standby SBC SWe instances.
• Place SBC SWe instances in different Availability Zones or on different hosts to protect against hardware failures.
• Use shared storage to store configuration and session data.
• Configure automatic failover and backup.
• Configure a monitoring and management system to quickly identify and resolve problems.
• Test HA regularly.
• Follow the SBC SWe HA configuration guidelines.

Implementing these recommendations will ensure high availability of SBC SWe in a cloud environment and guarantee uninterrupted operation of telecommunications services. Regular analysis and optimization of the HA configuration allows maintaining a high level of availability in the long term.