On the host machine I have install syslog. Now when I want to run docker on the same host machine what value do I put for syslog-address? How do I find the port that is assigned to the syslog?
docker run \
--log-driver syslog --log-opt syslog-address=udp://1.2.3.4:1111 \
alpine echo hello world
The default UDP syslog port is 514.
Check syslog-ng.conf to configure a different port/network source.
Related
I have docker for windows running windows container. Machine is connected to corporate network via Cisco AnyConnect VPN. We have been having this issue for sometime with no solutions. To explain the problem here is an example. Go to docker image here https://hub.docker.com/_/microsoft-dotnet-samples and run the below commands in command prompt / powershell in sequence
docker pull mcr.microsoft.com/dotnet/samples:aspnetapp
docker run -it --rm -p 8000:80 --name aspnetcore_sample mcr.microsoft.com/dotnet/samples:aspnetapp
replace port 8000 with something else if there is an error in lines of hns file being used. Go to browser and do http://localhost:8000 assuming its running on port 8000. It doesn't connect for me. Instead of localhost i also tried below command to find the ipaddress of the container running the image and then replace localhost with that ip address but with same response unable to connect.
docker inspect -f '{{range.NetworkSettings.Networks}}{{.IPAddress}}{{end}}' container_name_or_id
here is an screenshot of the network adapter docker sets up by default
here is another screenshot of the nat network adapter
I am running my code using MPI on a cluster. My code runs as a task in a docker running in swarm mode.
Steps I follow to run my code:
Create a overlay network
Run docker in swarm mode
Start a docker service (replicas = 4) using below command:
docker service create --name mpiser --network mpinet --replicas 4 mpitest:latest
My test code is a simple python script having:
from mpi4py import MPI
import subprocess
import time
comm = MPI.COMM_WORLD
sizeComm = comm.Get_size()
rank = comm.Get_rank()
while True:
print("Rank:",rank,"Hostname:",subprocess.check_output(['hostname']))
time.sleep(2)
I find the ip address of the tasks launched as part of the service
exec into one of the containers
create a "hosts" file with the ip addresses I found
Launch the test code using below command:
mpirun --allow-run-as-root -n 33 --hostfile hosts --mca btl_tcp_if_exclude eth1,lo python3 /home/test.py
This works fine and I can see the prints from all the containers within the swarm.
However, if I expose one of the ports while creating service with below command
docker service create --name mpiser -p 3000:3000 --network mpinet --replicas 4 mpitest:latest
The mpirun command fails with below errors:
------------------------------------------------------------
A process or daemon was unable to complete a TCP connection
to another process:
Local host: 8d3c60280396
Remote host: cc2da25814cc
This is usually caused by a firewall on the remote host. Please
check that any firewall (e.g., iptables) has been disabled and
try again.
------------------------------------------------------------
I tried using --mca btl_tcp_if_include to include only the interface that shows the ip address I added in the hosts file
I tried using --mca btl_tcp_if_exclude to exclued other interfaces that does not have the ip address I added in hosts file
Both these did not help.
Any suggestions on why exposing the port causes communication issue between the containers will be helpful
I have a proxy server which accepts connections on port 3459. When I am trying to connect to it from my local computer, I am able to connect. To test I ran this command in terminal:
curl --proxy http://proxy_url:3459 --proxy-user user:password -L icanhazip.com
When I tried to run the same in a GCP Compute Engine VM instance which lies in a non-default VPC (named testing-vpc), I'm unable to connect to the proxy.
I have created a firewall rule to open port 3459 by following command:
gcloud compute firewall-rules create proxy-allow-egress-port3459 \
--network testing-vpc \
--action allow \
--direction egress \
--rules tcp:3459 \
--destination-ranges 0.0.0.0/0 \
--priority 10 \
--target-tags testing-proxy
and attached the tag testing-proxy in my instance. Still, its not working. Please let me know what am I missing here.
You are creating an egress (--direction egress) rule, whereas you need an ingress rule to permit connections inbound destined to the GCE instance.
I'm running an nginx container on a windows 10 machine. I've stripped it down to a bare minimum - an nginx image provided in the Docker hub. I'm running it using:
docker run --name ng -d -P nginx
This is the output of docker ps:
b5411ff47ca6 nginx "nginx -g 'daemon off" 22 seconds ago Up 21 seconds 0.0.0.0:32771->80/tcp, 0.0.0.0:32770->443/tcp ng
And this is the IP I'm getting when doing docker inspect ng: "IPAddress": "172.17.0.2"
So, the next thing I'm trying to do is access the Nginx server from the host machine by opening http://172.17.0.2:32771 in browser of the host machine. This is not working (host not found etc).
Please advise
On windows, you are using Docker Toolbox, and the IP you need is 192.168.99.100 (which is the IP of the Docker Toolbox VM). The IP you got is the IP of the container inside the VM, which is not accessible directly from Windows.
Follow this article... https://docs.docker.com/get-started/part2/#run-the-app
And make sure your application is running not just docker.
docker run -d -p 4000:80 friendlyhello
After this on Windows 10 host machine
Worked http://192.168.99.100:4000/
Not working: http://localhost:4000/
I used the following command to map the internal port 80 on the running container to port 82 off localhost:
docker run --name webserver2 -d -p 82:80 nginx
accessing nginx image off localhost:82 works great.
The port you want to access from your local web browser is the first number before the :80 which is where nginx image runs virtually in the container.
There is lots of miscommunication out there on the issue -- it's a simple port mapping between the host machine (Windows you are running) and the container running on docker.
I have a running nginx container: # docker run --name mynginx1 -P -d nginx;
And got its PORT info by docker ps: 0.0.0.0:32769->80/tcp, 0.0.0.0:32768->443/tcp
Then I could get response from within the container(id: c30991a04b2f):
docker exec -i -t c3099 bash
curl http://localhost => which return the default index.html page content, it works
However, when I make the curl http://localhost:32769 outside of the container, I got this:
curl: (7) failed to connect to localhost port 32769: Connection refused
I am running on a mac with docker version 1.9.0; nginx latest
Does anyone know what cause this? Any help? thank you
If you are On OSX, you are probably using a VirtualBox VM for your docker environment.
Make sure you have forwarded your port 32769 to your actual host (the mac), in order for that port to be visible from localhost.
This is valid for the old boot2docker, or the new docker machine.
VBoxManage controlvm "boot2docker-vm" --natpf1 "tcp-port32769 ,tcp,,32769,,32769"
VBoxManage controlvm "boot2docker-vm" --natpf1 "udp-port32769 ,udp,,32769,,$32769
(controlvm if the VM is running, modifyvm is the VM is stopped)
(replace "boot2docker-vm" b ythe name of your vm: see docker-machine ls)
I would recommend to not use -P, but a static port mapping -p xxx:80 -p yyy:443.
That way, you can do that port forwarding once, using fixed values.
Of course, you can access the VM directly through docker-machine ip vmname
curl http://$(docker-machine ip vmname):32769
Solved.. I misunderstood how docker port mapping works.
Since I'm using mac, the host for nginx container is a VM, 0.0.0.0:32769->80/tcp maps the port 80 of the container to the port 32769 of the VM.
solution:
docker-machine ip vm-name => 192.168.99.xx
curl http://192.168.99.xx:32769
Not exactly answers for your question but spend some time trying to figure out similar thing in context of "why is my docker container not connecting to elastic search localhost:9200" and this was the first S.O. question that pops up, so I hope it helps some other googling person
if you are linking containers together (e.g. docker run --rm --name web2 --link db:db training/webapp env)
... then Dockers adds enviroment variables:
DB_NAME=/web2/db
DB_PORT=tcp://172.17.0.5:5432
DB_PORT_5432_TCP=tcp://172.17.0.5:5432
DB_PORT_5432_TCP_PROTO=tcp
DB_PORT_5432_TCP_PORT=5432
DB_PORT_5432_TCP_ADDR=172.17.0.5
... and also updates your /etc/hosts
# /etc/hosts
#...
172.17.0.9 db
so you can technically connect to ping db
https://docs.docker.com/v1.8/userguide/dockerlinks/
so for elastic search is
# /etc/hosts
# ...
172.17.0.28 elasticsearch f9db83d0dfb5 ecs-awseb-qa-3Pobblecom-env-f7yq6jhmpm-10-elasticsearch-fcbfe5e2b685d0984a00
so wget elasticseach:9200 will work