Sharding Collection Discovery for MongoDB 6.0+ Compatibility and RBAC Stability

[jaychakra]

Summary

This PR introduces two critical improvements to getMongoData.js:

1. MongoDB 6.0+ Support: Fixes missing sharding metadata caused by architectural changes in modern MongoDB versions.
2. RBAC Hardening: Improves script stability by skipping internal administrative collections that often trigger "Unauthorized" errors.

Feature 1: Fix Sharding Collection Discovery for MongoDB 6.0+

Problem

In MongoDB 6.0+, the partitioned field was removed from the config.databases collection. The legacy logic used if (db.partitioned) to gate collection discovery. Since this field is now undefined, the script incorrectly skips sharding information for modern clusters, leading to empty reports.

Solution

Updated the conditional check to if (db.partitioned !== false). This remains inclusive of undefined (modern) and true (legacy) while still respecting explicit false flags from older versions.

Compatibility Matrix

MongoDB Version	partitioned value	db.partitioned !== false	Result
Legacy (< 6.0)	true	true	Success
Legacy (< 6.0)	false	false	Skip
Modern (6.0+)	undefined	true	Success (Fixed)

Feature 2: Harden Collection Discovery Against Authorization Errors

Problem

When running with restricted RBAC (Role-Based Access Control), the script often encounters "Unauthorized" errors when trying to access internal logs (e.g., local.startup_log) or replica set metadata. These errors can cause the script to terminate prematurely or produce noisy, invalid JSON output.

Solution

Expanded the collection exclusion list in printDataInfo. In addition to system.*, the script now explicitly skips:

• replicaset*
• startup_log*
• replset*

Code Changes Summary

File: getMongoData.js

// 1. Sharding Fix
- if (db.partitioned) {
+ if (db.partitioned !== false) {

// 2. Authorization Hardening
- if (!name.startsWith("system.")) {

+ // Always filter out "system." collections across all databases.
+ if (name.startsWith("system.")) {
+    return;
+ }

+ // Filter MongoDB-internal replication metadata collections, but ONLY
+ // in the "local" database, to avoid dropping legitimate user
+ // collections (e.g., app.replsetEvents, app.startup_log_archive)
+ // that happen to share a similar name in user databases.
+ if (mydb.name === "local") {
+     if (name === "startup_log" || name.startsWith("replset.")) {
+        return;
+    }
+}

Verification

• Validated against MongoDB 8.0.23 where the partitioned field is absent.
• Confirmed successful completion RS and Sharded environments with auth enabled

[Copilot]

Pull request overview

This PR updates the getMongoData Mongo shell script to better report sharding metadata on MongoDB 6.0+ clusters and to reduce failures/noise under restricted RBAC by skipping certain internal collections during data collection.

Changes:

• Adjust sharded database detection to treat partitioned: undefined (MongoDB 6.0+) as eligible for sharding collection discovery.
• Expand collection filtering in printDataInfo to skip additional internal collections that commonly trigger authorization errors.
• Bump script version from 4.1.1 to 4.1.2.

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.