Docs for SERVER-37823: Server Side Traffic Capture

Description

Description:

Documentation for MongoTrafficReader

Preliminary docs changes: https://github.com/tkaye407/docs/commit/20369b1e89a3b475ac2dd2bcc30c3fd76de99210

There are two sections of the documentation that need to be edited / added

1. Add Commands startRecordingTraffic and stopRecordingTraffic
Notes:
mongod must be run with --setParameter="trafficRecordingDirectory=..."
dir above must exist and cannot have ~/ stuff
Only on admin database
Must have clusterManager role (hostManager)
Issues warning: *** important
Warning: the recording file contains unencrypted user traffic, we recommend that you limit retention of this file and store it on an encrypted filesystem volume.
Comment about the performance?

Parameters for startRecordingTraffic():
a. filename: string --> required
b. bufferSize: int64 --> default = 134217728 (128MiB)
c. maxFileSize: int64 --> default = 4294967296 (4GiB)

stopRecordingTraffic()
returns any errors that may have happened while recording

2. Server Sytatus New Fields:
"running" : <boolean>
"bufferSize" : NumberLong(<num>)
"bufferedBytes" : NumberLong(<num>)
"recordingFile" : <string>
"maxFileSize" : NumberLong(<num>)
"currentFileSize" : NumberLong(<num>)

Engineering Ticket Description:

Provide a mechanism for capturing client traffic sent to a mongo[d|s] process by observing and copying the messages after they’ve transited the transport layer – i.e. after operating system ::recv() and subsequent TLS decryption. This allows the use of mongoreplay and other tee like functionality to be used when TLS is enabled for client/server communication.

Scope of changes

*note:* mongoreplay will be updated to be able to read the captured traffic file (TOOLS-2201) For now, will only add a little blurb. When TOOLS-2201 finishes, will need to revamp the mongoreplay page.

• source/reference/built-in-roles.txt
• source/reference/command/serverStatus.txt
• source/reference/command/startRecordingTraffic.txt
• source/reference/command/stopRecordingTraffic.txt
• source/reference/parameters.txt
• source/reference/program/mongoreplay.txt (More to come when TOOLS-2201 completes – See DOCS-12506)
• source/release-notes/4.2.txt
• redirects

Impact to Other Docs

probably Atlas

MVP (Work and Date)

Resources (Scope or Design Docs, Invision, etc.)