B.net Index Server 2 -

Unveiling B.net Index Server 2: The Backbone of Modern Battle.net Infrastructure

Providing a central repository for common utility software and drivers. B.net Index Server

The Three Pillars of BIS2

Introduction: What is B.net Index Server 2?

Index Server 2

The is the secondary iteration of this discovery service. Its primary job was simple but vital: maintain a real-time list of active game lobbies (for titles like Diablo II , Warcraft III , and StarCraft ) and direct connecting clients to the correct IP addresses of the game hosts. B.net Index Server 2

• Proprietary binary indexes – Highly optimized for Boolean, proximity, and fielded searches.
• Multi-threaded – Could handle hundreds of concurrent users on mid-range UNIX or Windows NT servers.
• No native full-text SQL support – Used its own query language (BRS Query Language).

• Slow queries: capture query profile, check for high shard scatter, examine hot spots, check merges and GC.
• Indexing backlog: verify WAL usage, check replication lag, ensure ingest threadpools are not saturated.
• Disk pressure: identify largest indices/segments, apply retention, increase capacity, or move shards.
• Replica not catching up: check network, WAL availability, and leader health; consider restarting replica after ensuring data safety.
• Cluster instability: check coordinator logs, election churn, and configuration changes; examine metadata corruption if frequent.

One of the critical functions of the Index Server during this era was managing "Realm" characters. While StarCraft used peer-to-peer connections for gameplay, Diablo II introduced closed Battle.net realms where characters were stored server-side. The Index Server had to coordinate with the database servers to ensure that only valid characters with legitimate items could join or create games—a frontline defense against the rising tide of duping and hacking. Unveiling B