Redis service is not starting on windows 10. pls help.
redis.windows-service-redis1.conf :-
bind 127.0.0.1
port 6379
command :-
sc create RedisM DisplayName= "RedisM" binPath= "\"redis-server.exe\" –service-install \"redis.windows-service-redis1.conf\"
Related
I'm running Scylladb locally in a docker container and I want to access the cluster outside the docker container. That's when I'm getting the following error: cassandra.cluster.NoHostAvailable: ('Unable to connect to any servers')
Datacenter: datacenter1
=======================
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
-- Address Load Tokens Owns Host ID Rack
UN 172.17.0.2 776 KB 256 ? ad698c75-a465-4deb-a92c-0b667e82a84f rack1
Note: Non-system keyspaces don't have the same replication settings, effective ownership information is meaningless
Cluster Information:
Name: Test Cluster
Snitch: org.apache.cassandra.locator.SimpleSnitch
DynamicEndPointSnitch: disabled
Partitioner: org.apache.cassandra.dht.Murmur3Partitioner
Schema versions:
443048b2-c1fe-395e-accd-5ae9b6828464: [172.17.0.2]
I have no problem accessing the cluster using cqlsh on port 9042:
Connected to at 172.17.0.2:9042.
[cqlsh 5.0.1 | Cassandra 3.0.8 | CQL spec 3.3.1 | Native protocol v4]
Now I'm trying to access the cluster from my fastapi app that is outside the docker container.
from cassandra.cluster import Cluster
cluster = Cluster(['172.17.0.2'])
session = cluster.connect('Test Cluster')
And here's the Error that I'm getting:
raise NoHostAvailable("Unable to connect to any servers", errors)
cassandra.cluster.NoHostAvailable: ('Unable to connect to any servers', {'172.17.0.2:9042': OSError(51, "Tried connecting to [('172.17.0.2', 9042)]. Last error: Network is unreachable")})
with a little bit of tinkering, it's possible to achieve a connection to the Scylla running in a container outside of the container for local development.
I've tried on M1 Mac with docker desktop:
Run scylla container with couple of new parameters[src]:
--listen-address 0.0.0.0 for simplification as we are spawning Scylla inside the container to allow connection to the container from any network
--broadcast-rpc-address 127.0.0.1 required if --listen-address set to 0.0.0.0. We are going to port forward 9042 from container to host (local) machine, so this is an IP where it will be acessible.
The final command to spawn the container is:
$ docker run --rm -ti \
-p 127.0.0.1:9042:9042 \
scylladb/scylla \
--smp 1 \
--listen-address 0.0.0.0 \
--broadcast-rpc-address 127.0.0.1
The -p 127.0.0.1:9042:9042 is to make port 9042 accessible on host (local) machine.
Install pip3 install scylla-driver as it has support of darwin/arm64 architecture.
Write a simple python script:
# so74265199.py
from cassandra.cluster import Cluster
cluster = Cluster(['127.0.0.1'])
session = cluster.connect()
# Select from a table that is available without keyspace
res = session.execute('SELECT * FROM system.versions')
print(res.one())
Run your script
$ python3 so74265199.py
Row(key='local', build_id='71178cf6db7021896cd8251751b78b3d9e3afa8d', build_mode='release', version='5.0.5-0.20221009.5a97a1060')
Disclaimer: I'm not an expert in Scylla's configuration, so feel free to point out a better approach.
So I have a Spark cluster running in Docker using Docker Compose. I'm using docker-spark images.
Then i add 2 more containers, 1 is behave as server (plain python) and 1 as client (spark streaming app). They both run on the same network.
For server (plain python) i have something like
import socket
s.bind(('', 9009))
s.listen(1)
print("Waiting for TCP connection...")
while True:
# Do and send stuff
And for my client (spark app) i have something like
conf = SparkConf()
conf.setAppName("MyApp")
sc = SparkContext(conf=conf)
sc.setLogLevel("ERROR")
ssc = StreamingContext(sc, 2)
ssc.checkpoint("my_checkpoint")
# read data from port 9009
dataStream = ssc.socketTextStream(PORT, 9009)
# What's PORT's value?
So what is PORT's value? is it the IP Adress value from docker inspect of the container?
Okay so i found that i can use the IP of the container, as long as all my containers are on the same network.
So i check the IP by running
docker inspect <container_id>
and check the IP, and use that as host for my socket
Edit:
I know it's kinda late, but i just found out that i can actually use the container's name as long as they're in the same network
More edit:
i made changes in docker-compose like:
container-1:
image: image-1
container_name: container-1
networks:
- network-1
container-2:
image: image-2
container_name: container-2
ports:
- "8000:8000"
networks:
- network-1
and then in my script (container 2):
conf = SparkConf()
conf.setAppName("MyApp")
sc = SparkContext(conf=conf)
sc.setLogLevel("ERROR")
ssc = StreamingContext(sc, 2)
ssc.checkpoint("my_checkpoint")
# read data from port 9009
dataStream = ssc.socketTextStream("container-1", 9009) #Put container's name here
I also expose the socket port in Dockerfile, I don't know if that have effect or not
I have tried to setup a Redis cluster running docker but it hangs when I try to join them. My docker ps gives me this:
Notice the port mapping.
All containers have this basic redis.conf file
port 6379
cluster-enabled yes
cluster-config-file nodes.conf
cluster-node-timeout 5000
appendonly yes
cluster-announce-ip 127.0.0.1
cluster-announce-port [7001, 7002, 7003, 7004, 7005 or 7006]
cluster-announce-bus-port [7101, 7102, 7103, 7104, 7105 or 7106]
Where the only change is the cluster-announce-port and cluster-announce-bus-port for each docker container. I hope you get the point.
I try to join the nodes with ./redis-trib.rb create --replicas 1 127.0.0.1:7001 127.0.0.1:7002 127.0.0.1:7003 127.0.0.1:7004 127.0.0.1:7005 127.0.0.1:7006
And it discovers it perfectly and asking if the config should be accepted:
But then redis-trib hangs indefinitely with "Waiting for the cluster to join". I can see through docker logs r_1 to r_6, that the epoch is getting set:
1:M 15 Jul 10:38:08.493 # configEpoch set to 1 via CLUSTER SET-CONFIG-EPOCH
So redis-trib does call the different nodes.
I cant really find anything about the cluster-announce variables anywhere. Does anyone here know how to do this? I think my problems lies in this part.
The redis version I am using is 4.0.10.
Ok so I figured it out. I needed to
set my cluster-announce-ip to the Ethernet adapter that has been created when installing docker (open up a terminal and do ipconfig)
update redis-trib.rb to reflect this IP
map the 16379 port when the docker image is created
I have set of microservices running as docker container. One microservice say A wants to connect to cassnadra running locally on my laptop. in order to do so i have below configurations
snippet from yaml file of service A
cassandra:
hosts: [127.0.0.1]
keyspace: "My keyspace"
protocol_version: 3
ports: 9042
In other side i ran cassandra by calling ./bin/cassandra . and then i connected to cqlsh locally whose output is as below
Connected to Test Cluster at 127.0.0.1:9042.
[cqlsh 5.0.1 | Cassandra 3.0.6 | CQL spec 3.4.0 | Native protocol v4]
Use HELP for help.
now when my container comes up and try to connect to this running cassandra hosted on my machine it says as says connection refused . please see the trace below
File "cassandra/cluster.py", line 2076, in cassandra.cluster.ControlConnection._reconnect_internal (cassandra/cluster.c:36914)
cassandra.cluster.NoHostAvailable: ('Unable to connect to any servers', {'127.0.0.1': ConnectionRefusedError(111, "Tried connecting to [('127.0.0.1', 9042)]. Last error: Connection refused")})
[start] application exit with code 1, killing container
more info
I am using apache-cassandra-3.0.6.
Please advise. Thanks
As Shibashis has mentioned, probably you cannot reach the host via docker container with 127.0.0.1
Please find the IP represented as HOST.
How to get the IP address of the docker host from inside a docker container
Start the cassandra instance by changing the conf\cassandra.yaml
listen_address
rpc_address
to the recongnized HOST IP.
Hope it helps!
I havs migrated my Rails app (local dev machine) to Docker-Compose. All is working except the Worker Rails instance (batch) cannot connect to Redis.
Completed 500 Internal Server Error in 40ms (ActiveRecord: 2.3ms)
Redis::CannotConnectError (Error connecting to Redis on 127.0.0.1:6379 (Errno::ECONNREFUSED)):
In my docker-compose.yml
redis:
image: redis
ports:
- "6379:6379"
batch:
build: .
command: bundle exec rake environment resque:work QUEUE=*
volumes:
- .:/app
links:
- db
- redis
environment:
- REDIS_URL=redis://redis:6379
I think the Redis instance is available via the IP of the Docker host.
$ docker-machine ls
NAME ACTIVE DRIVER STATE URL SWARM DOCKER ERRORS
default * virtualbox Running tcp://192.168.99.100:2376 v1.10.0
Accessing via 0.0.0.0 doesn't work
$ curl 0.0.0.0:6379
curl: (7) Failed to connect to 0.0.0.0 port 6379: Connection refused
Accessing via the docker-machine IP I think works:
$ curl http://192.168.99.100:6379
-ERR wrong number of arguments for 'get' command
-ERR unknown command 'Host:'
EDIT
After installing redis-cli in the batch instance, I was able to hit the redis server using the 'redis' hostname. I think the problem is possibly in the Rails configuration itself.
Facepalm!!!
The docker containers were communicating just fine, the problem was I hadn't told Resque (the app using Redis) where to find it. Thank you to "The Real Bill" for pointing out I should be using docker-cli.
For anyone else using Docker and Resque, you need this in your config/initializers/resque.rb file:
Resque.redis = Redis.new(host: 'redis', port: 6379)
Resque.after_fork = Proc.new { ActiveRecord::Base.establish_connection }
If you run
docker-compose run --rm batch env | grep REDIS
you will get the env variables that your container has (the link line in the compose will auto-generate some).
Then all you need to do is look for one along the lines of _REDIS_1_PORT... and use the correct one. I have never had luck connecting my rails to another service in any other way. But luckily these env variables are always generated on start so they will be up to date even if the container IP happens to change between startups.
You should use the hostname redis to connect to the service, although you may need to wait for redis to start.