Mirror Redis Traffic to another redis node

redis-mirror

Realtime Redis Traffic Mirror to another instance, this script reads the STDOUT from the redis-cli monitor command and mirrors the keys to another instance.

Use Case/Note

In some production/development cases, you need to mirror Redis traffic to another node to do some investigation or debugging.

• This script does not set TTL to mirrored key since you need it for debugging.
• The script support all command since it simply dump and restore the key as is.

TO DO:

1. Add TTL as an option in mirrored redis instance, plus add an option to expand the origin TTL.
2. Support cluster to a single redis instance or vice versa.
3. Add an option to dump all keys name to the file for further analysis.
4. Add an option to get all keys from the source and migrate the keys to another redis instance.

Option

redismirror --help
Usage: redismirror [OPTIONS]

Options:
  --shost TEXT     Source redis host/IP.
  --sport INTEGER  Source redis port.
  --sdb INTEGER    Source redis DB.
  --sauth TEXT     Source redis auth info.
  --dhost TEXT     Destination redis host/IP.
  --dport INTEGER  Destination redis port.
  --ddb INTEGER    Destination redis DB.
  --dauth TEXT     Destination redis auth info.
  --limit INTEGER  Stop mirror process at limit X.
  --replace        Replace key if exists.
  --help           Show this message and exit.

Useages

redis-cli monitor | redismirror  --sport 6379 --shost localhost  --dhost 127.0.0.1 --dport 6379

#Exmaple 2
redis-cli monitor |  redismirror  --shost localhost --dport 6377  --limit 100

Exmaple output:

$ redis-cli monitor | redismirror  --sport 6379 --shost localhost  --dhost 127.0.0.1 --dport 6378 --replace  --ttl --ttle 10 --limit 10

onnected to Redis: Host: localhost, Port: 6379, DB: 0
Connected to Redis: Host: 127.0.0.1, Port: 6378, DB: 0
✔  Mirrored key | Key: e2657ecd-6ee0-4182-9128-239be76cbba5_1679609769_json, TTL: 10, Status: OK - Command SET
☀  Skipping Key -> DUMP, Key -> e2657ecd-6ee0-4182-9128-239be76cbba5_1679609769_json
✔  Mirrored key | Key: e2657ecd-6ee0-4182-9128-239be76cbba5_1679609769_image_base64, TTL: 10, Status: OK - Command SET
☀  Skipping Key -> TTL, Key -> e2657ecd-6ee0-4182-9128-239be76cbba5_1679609769_json
✔  Mirrored key | Key: e2657ecd-6ee0-4182-9128-239be76cbba5_key1, TTL: 10, Status: OK - Command MSET
✔  Mirrored key | Key: e2657ecd-6ee0-4182-9128-239be76cbba5_setnx_key, TTL: 10, Status: OK - Command SETNX
✔  Mirrored key | Key: e2657ecd-6ee0-4182-9128-239be76cbba5_setex_key, TTL: 20, Status: OK - Command SETEX
☀  Skipping Key -> DUMP, Key -> e2657ecd-6ee0-4182-9128-239be76cbba5_1679609769_image_base64
✔  Mirrored key | Key: e2657ecd-6ee0-4182-9128-239be76cbba5_psetex_key, TTL: 20, Status: OK - Command PSETEX
☀  Skipping Key -> TTL, Key -> e2657ecd-6ee0-4182-9128-239be76cbba5_1679609769_image_base64
✔  Mirrored key | Key: e2657ecd-6ee0-4182-9128-239be76cbba5_getset_key, TTL: 10, Status: OK - Command GETSET
✔  Mirrored key | Key: e2657ecd-6ee0-4182-9128-239be76cbba5_hash, TTL: 10, Status: OK - Command HSET
✔  Mirrored key | Key: e2657ecd-6ee0-4182-9128-239be76cbba5_hash_multi, TTL: 10, Status: OK - Command HSET
✔  Mirrored key | Key: e2657ecd-6ee0-4182-9128-239be76cbba5_hash_setnx, TTL: 10, Status: OK - Command HSETNX
Limit reached: 10

Installation using pypi

pip install redismirror

Installation

$ pip install -r requirements.txt

$ pip install setup.py

Development

This project includes a number of helpers in the Makefile to streamline common development tasks.

Environment Setup

The following demonstrates setting up and working with a development environment:

### create a virtualenv for development

$ make virtualenv
Or
$ python3 -m venv env
then
$ source env/bin/activate
$ pip install -r requirements.txt

$ pip install setup.py

### run redismirror cli application

$ redismirror --help


### run pytest / coverage

$ make test

Releasing to PyPi

Before releasing to PyPi, you must configure your login credentials:

~/.pypirc:

[pypi]
username = YOUR_USERNAME
password = YOUR_PASSWORD

Then use the included helper function via the Makefile:

$ make dist

$ make dist-upload

Deployments

Docker

Included is a basic Dockerfile for building and distributing Redis Mirror , and can be built with the included make helper:

$ make docker

$ docker run -it redismirror --help

Extra

To Generate sample data for your test using the below command:

cd tests/Generator/;bash SampleDataInserter.sh

# Or Using python script
# Make sure to update config in the same file
python fillRedis.py

The following commands are also not logged:

skip_commands_list = [
    'FLUSHDB', 'INFO', 'FLUSHALL', 'AUTH', 'QUIT', 'SELECT', 'CLIENT', 'ROLE',
    'BGREWRITEAOF', 'TIME', 'ECHO', 'CONFIG', 'MONITOR', 'SYNC', 'SHUTDOWN',
    'DBSIZE', 'DEBUG', 'COMMAND', 'SCRIPT', 'SAVE', 'OBJECT', 'SLAVEOF',
    'KEYS', 'BGSAVE', 'SCAN', 'DUMP', 'SLOWLOG', 'TTL', 'PING', 'LASTSAVE'
]

Cost of running MONITOR Because MONITOR streams back all commands, its use comes at a cost. The following (totally unscientific) benchmark numbers illustrate what the cost of running MONITOR can be.

Benchmark result without MONITOR running:

$ src/redis-benchmark -c 10 -n 100000 -q
PING_INLINE: 101936.80 requests per second
PING_BULK: 102880.66 requests per second
SET: 95419.85 requests per second
GET: 104275.29 requests per second
INCR: 93283.58 requests per second

Benchmark results with MONITOR running (redis-cli monitor > /dev/null):

$ src/redis-benchmark -c 10 -n 100000 -q
PING_INLINE: 58479.53 requests per second
PING_BULK: 59136.61 requests per second
SET: 41823.50 requests per second
GET: 45330.91 requests per second
INCR: 41771.09 requests per second

In this particular case, running a single MONITOR client can reduce the throughput by more than 50%. Running more MONITOR clients will reduce throughput even more.

License

GNU GENERAL PUBLIC LICENSE

Author Information

The tool was originally developed by Ali Saleh Baker.