Simulate Redis Faults

This document introduces how to use Chaosd to simulate Redis faults. This feature uses Golang interfaces in go-redis package and the redis-server command-line tool. You can create experiments either in command-line mode or service mode.

Create experiments using command-line mode

Before creating an experiment, you can run the following command to see the Redis fault types that are supported by Chaosd:

chaosd attack redis -h

The result is as follows:

Redis attack related commands
Usage:
  chaosd attack redis [command]
Available Commands:
  cache-expiration  expire keys in Redis
  cache-limit       set maxmemory of Redis
  cache-penetration penetrate cache
  sentinel-restart  restart sentinel
  sentinel-stop     stop sentinel
Flags:
  -h, --help   help for redis
Global Flags:
      --log-level string   the log level of chaosd. The value can be 'debug', 'info', 'warn' and 'error'
      --uid string         the experiment ID
Use "chaosd attack redis [command] --help" for more information about a command.

Currently, Chaosd supports simulating cache expiration, cache penetration, cache limit, sentinel restart, and sentinel stop.

Simulate cache expiration using command-line mode

The meaning of this command is the same as EXPIRE in Redis. For more details, refer to the Redis official documentation.

note

Currently, Chaosd does not support recovering keys that have executed cache-expiration, so please backup them in advance if you want to recover them.

Commands for cache expiration

chaosd attack redis cache-expiration -h

The result is as follows:

expire keys in Redis
Usage:
  chaosd attack redis cache-expiration [flags]
Flags:
  -a, --addr string         The address of redis server
      --expiration string   The expiration of the key. A expiration string should be able to be converted to a time duration, such as "5s" or "30m" (default "0")
  -h, --help                help for cache-expiration
  -k, --key string          The key to be set a expiration, default expire all keys
      --option string       The additional options of expiration, only NX, XX, GT, LT supported
  -p, --password string     The password of server
Global Flags:
      --log-level string   the log level of chaosd. The value can be 'debug', 'info', 'warn' and 'error'
      --uid string         the experiment ID

Configuration description for cache expiration

Example for simulating cache expiration

chaosd attack redis cache-expiration -a 127.0.0.1:6379 --option GT --expiration 1m

Simulate cache limit using command-line mode

Commands for cache limit

chaosd attack redis cache-limit -h

The result is as follows:

set maxmemory of Redis
Usage:
  chaosd attack redis cache-limit [flags]
Flags:
  -a, --addr string       The address of redis server
  -h, --help              help for cache-limit
  -p, --password string   The password of server
      --percent string    The percentage of maxmemory
  -s, --size string       The size of cache (default "0")
Global Flags:
      --log-level string   the log level of chaosd. The value can be 'debug', 'info', 'warn' and 'error'
      --uid string         the experiment ID

Configuration description for cache limit

Example for simulating cache limit

chaosd attack redis cache-limit -a 127.0.0.1:6379 -s 256M

Simulate cache penetration using command-line mode

This command will send the specified number of GET requests to Redis server as quickly as possible using Redis Pipeline. Since the requested keys do not exist on the Redis server, these requests will cause a cache penetration phenomenon.

Commands for cache penetration

chaosd attack redis cache-penetration -h

The result is as follows:

penetrate cache
Usage:
  chaosd attack redis cache-penetration [flags]
Flags:
  -a, --addr string       The address of redis server
  -h, --help              help for cache-penetration
  -p, --password string   The password of server
      --request-num int   The number of requests
Global Flags:
      --log-level string   the log level of chaosd. The value can be 'debug', 'info', 'warn' and 'error'
      --uid string         the experiment ID

Configuration description for cache penetration

Example for simulating cache penetration

chaosd attack redis cache-penetration -a 127.0.0.1:6379 --request-num 100000

Simulate Sentinel restart using command-line mode

Commands for Sentinel restart

chaosd attack redis sentinel-restart -h

The result is as follows:

restart sentinel
Usage:
  chaosd attack redis sentinel-restart [flags]
Flags:
  -a, --addr string         The address of redis server
  -c, --conf string         The config of Redis server
      --flush-config         Force Sentinel to rewrite its configuration on disk (default true)
  -h, --help                help for sentinel-restart
  -p, --password string     The password of server
      --redis-path string   The path of the redis-server command
Global Flags:
      --log-level string   the log level of chaosd. The value can be 'debug', 'info', 'warn' and 'error'
      --uid string         the experiment ID

Configuration description for Sentinel restart

Example for simulating Sentinel restart

chaosd attack redis sentinel-restart -a 127.0.0.1:26379 --conf /home/redis-test/sentinel-26379.conf

Simulate Sentinel stop using command-line mode

Commands for Sentinel stop

chaosd attack redis sentinel-stop -h

The result is as follows:

stop sentinel
Usage:
  chaosd attack redis sentinel-stop [flags]
Flags:
  -a, --addr string         The address of redis server
  -c, --conf string         The config path of Redis server
      --flush-config        Force Sentinel to rewrite its configuration on disk (default true)
  -h, --help                help for sentinel-stop
  -p, --password string     The password of server
      --redis-path string   The path of the redis-server command
Global Flags:
      --log-level string   the log level of chaosd. The value can be 'debug', 'info', 'warn' and 'error'
      --uid string         the experiment ID

Configuration description for Sentinel stop

Example for simulating Sentinel restart

chaosd attack redis sentinel-stop -a 127.0.0.1:26379 --conf /home/redis-test/sentinel-26379.conf

Create Redis fault experiments using service mode

To create experiments using the service mode, follow the instructions below:

1. Run Chaosd in the service mode:

   chaosd server --port 31767

2. Send a POST HTTP request to the /api/attack/redis path of the Chaosd service.

   curl -X POST 127.0.0.1:31767/api/attack/redis -H "Content-Type:application/json" -d '{fault-configuration}'

   In the above command, you need to configure fault-configuration according to the fault types. For the corresponding parameters, refer to the parameters and examples of each fault type in the following sections.

note

When running an experiment, remember to record the UID of the experiment. When you want to end the experiment corresponding to the UID, you need to send a DELETE HTTP request to the /api/attack/{uid} path of the Chaosd service.

Simulate cache expiration using service mode

Parameters for simulating cache expiration

Example for simulating cache expiration using service mode

curl -X POST 127.0.0.1:31767/api/attack/redis -H "Content-Type:application/json" -d '{"action":"expiration", "expiration":"1m","addr":"127.0.0.1:6379"}'

Simulate cache limit using service mode

Parameters for simulating cache limit

Example for simulating cache limit using service mode

curl -X POST 127.0.0.1:31767/api/attack/redis -H "Content-Type:application/json" -d '{"action":"cacheLimit", ""addr":"127.0.0.1:6379", "percent":"50%"}'

Simulate cache penetration using service mode

Parameters for simulating cache penetration

Example for simulating cache penetration using service mode

curl -X POST 127.0.0.1:31767/api/attack/redis -H "Content-Type:application/json" -d '{"action":"penetration", ""addr":"127.0.0.1:6379", "request-num":"10000"}'

Simulate Sentinel restart using service mode

Parameters for simulating Sentinel restart

Example for simulating Sentinel restart using service mode

curl -X POST 127.0.0.1:31767/api/attack/redis -H "Content-Type:application/json" -d '{"action":"restart", ""addr":"127.0.0.1:26379", "conf":"/home/redis-test/sentinel-26379.conf"}'

Simulate Sentinel stop using service mode

Parameters for simulating Sentinel stop

Example for simulating Sentinel stop using service mode

curl -X POST 127.0.0.1:31767/api/attack/redis -H "Content-Type:application/json" -d '{"action":"stop", ""addr":"127.0.0.1:26379", "conf":"/home/redis-test/sentinel-26379.conf"}'