I am trying to send a message to RabbitMQ via MQTT, however when the connection is established, the channel shows that is has ... no consumers .... To my understanding, upon connecting via MQTT to RabbitMQ, the topic will default to the amq.topic, and a new queue will be created for these connections.
Oddly enough, this does happen when I connect using Mosquitto, however, other MQTT clients do not get their own queue.
So, as an example, connecting like so: mosquitto_sub -h rabbit-01.<hostname.com> -p 1883 -u <v_host>:<username> -P <pass> -t "#"
produces:
HOWEVER!
my connection from the other server pub/sub mqtt integration thing results in no new queue displaying. Here are the settings for that:
Any help would be greatly apprecieated!
Thanks!
Related
I have been researching this Redis error for days now...
I created a GCP Memorystore Redis instance and received the following internal IP endpoint:
10.xxx.xxx.xxx:6378
I created a small GCE instance and made sure that zone matched the Redis instance:
us-central1-f
However, I when I ssh into the VM, connect to Redis, and issue a PING, I get the following error response
Protocol error, got "\x15" as reply type byte
Any idea why I am getting this error?
If the Redis instance was configured with an AUTH string and/or TLS encryption, you would need to pass these credentials when connecting to it.
I received the same error when using your command to connect to my encrypted instance. This can be done in two ways as far as I tested (from a GCE instance in the same VPC as Redis):
1. Using the redis-cli, you could use the following command to authenticate (see here for information on the flags used in the command):
redis-cli -h <ip_addres> -p <port> -a <auth_string> --tls --cacert <path/to/certificate_file.pem>
Note: the certificate file would need to be installed to your VM.
2. The GCP Memorystore documentation recommends using telnet and Stunnel to connect to a secured and encrypted instance.
Something not included in the documentation is that after running telnet localhost 6378 in step 4, you would need to pass the AUTH string in the telnet console:
AUTH <auth_string>
+OK
PING
+PONG
After that, you can PING the instance in step 5, skipping sending the AUTH string will return this error: -NOAUTH Authentication required. Besides that, you should follow as documented the rest of the steps.
I have created a redis memcached database on https://app.redislabs.com/ and trying to connect to that using command line. I am using:
redis-cli -h <HOST> -p <PORT> -a <Password>
But it keeps returning:
Could not connect to Redis at <HOST:PORT>: Operation timed out
Do we need to do any additional configurations to connect to Redis cloud server?
This is the timeout error which means the redis instance is not reachable from your machine. Make sure the traffic is allowed from your machine to the redislab. In redislab you can define the network range for connectivity.
Also try to telnet to the port,telnet <HOST> <PORT> if its not connecting then its the connectivity issue only.
I am trying to create a bridge with Azure IoT Hub.
The configuration of mosquitto bridge is following:
connection Azure
address <my_hub_name>.azure-devices.net:8883
# error | information | notice | warning | all | debug
log_dest stdout
log_type all
## Auth Info
remote_username <my_hub_name>.azure-devices.net/<my_dev_name>/?api-version=2018-06-30
remote_password <SAS>
remote_clientid <my_dev_name>
bridge_cafile cert.pem
## some config
try_private false
cleansession true
start_type automatic
bridge_insecure false
bridge_protocol_version mqttv311
bridge_tls_version tlsv1.2
notifications false
## Topics
topic devices/<my_dev_name>/messages/events/# out
And I get the following output:
Opening ipv6 listen socket on port 1883.
Bridge local.<my_dev_name> doing local SUBSCRIBE on topic devices/<my_dev_name>/messages/events/#
Connecting bridge Azure (<my_hub_name>.azure-devices.net:8883)
Bridge <my_dev_name> sending CONNECT
Received CONNACK on connection local.<my_dev_name>.
Bridge local.<my_dev_name> sending UNSUBSCRIBE (Mid: 1, Topic: devices/<my_dev_name>/messages/events/#)
Received UNSUBACK from local.<my_dev_name>
Socket error on client local.<my_dev_name>, disconnecting.
Bridge local.<my_dev_name> doing local SUBSCRIBE on topic devices/<my_dev_name>/messages/events/#
Connecting bridge Azure (<my_hub_name>.azure-devices.net:8883)
Bridge <my_dev_name> sending CONNECT
Received CONNACK on connection local.<my_dev_name>.
Bridge local.<my_dev_name> sending UNSUBSCRIBE (Mid: 1, Topic: devices/<my_dev_name>/messages/events/#)
Received UNSUBACK from local.<my_dev_name>
Socket error on client local.<my_dev_name>, disconnecting.
...
Wireshark shows that for unknown reason Azure sends me a packet with FIN bit set, which results into connection reset.
At the same time mosquitto_pub is able to send a packet with same parameters (host, username, password). The utility mosquitto_sub also works without errors, but does not receive any of messages published by mosquitto_pub.
Spent several days trying to figure out the correct configuration without any success (including, of course, search on stackoverflow). I will be very appreciated for any hints.
As far as I know, nobody could connect to our IoT Hub before, so probably there maybe an issue with created hub. Unfortunately, learn.microsoft.com looks more like a quest rather than a help.
EDITED: corrected the topic parameter in configuration from "in" to "out".
As inferred from the comments.
The problem will be that the 2 bridges will have generated the same client id.
Client IDs need to be unique across all clients connected to the broker. If a second client connects with the same client id the spec says the broker must disconnect the fist one.
The disconnected client then tries to reconnect and this results in the other broker being kicked off, which then starts a feedback loop with each client kicking the other off as it reconnects.
Almost all connection errors were resolved by accurate setup of certificate and broker configuration. Except one and its description follows.
We create a bridge with above credentials (certificate, SAS login/password/clientid) - everything works fine.
The bridge is configured with following topic rule:
topic # both 0 /devices/ devices/<my_dev_name>/messages/events/
If I publish the following to my local broker:
mosquitto_pub \
-h 10.0.2.15 -p 1883 \
-t "/devices/foobar" \
-m "{\"foo\" : \"bar\"}" \
-d
everything is fine. But if I publish a bit more long topic
mosquitto_pub \
-h 10.0.2.15 -p 1883 \
-t "/devices/foo/foobar" \
-m "{\"foo\" : \"bar\"}" \
-d
I get connection reset error:
1607623721: Received PUBLISH from mosq-52yqOrz6C6riwvUUF3 (d0, q0, r0, m0, '/devices/foo/foobar1', ... (16 bytes))
1607623721: Sending PUBLISH to local.<my_dev_name> (d0, q0, r0, m0, 'devices/<my_dev_name>/messages/events/foo/foobar1', ... (16 bytes))
1607623721: Received DISCONNECT from mosq-52yqOrz6C6riwvUUF3
1607623721: Client mosq-52yqOrz6C6riwvUUF3 disconnected.
1607623721: Socket error on client local.<my_dev_name>, disconnecting.
I do not understand why Azure disconnects my bridge. I can make about a hundred messages to the topic /devices/foobar in 2-3 seconds without any complaints, but only one message to /devices/foo/foobar results into immediate socket error.
Probably, there is some restriction, but I can not find any of them, except the total maximum number of messages during one day.
I want to fetch the last / latest message added in the queue, is there a specific option available in the rabbitmqadmin utility.
The following command is giving the first message in the queue,
./rabbitmqadmin get queue='log' -H localhost -P 15672 -u <username> -p <password> --vhost=logging count=1
Are you looking to consume or view the messages? I use this tool plumber to view the latest incoming messages without removing them from the queue. If you are looking to consume just the latest message you may have to write a script.
To read the latest inbound message and exit:
plumber read messages rabbitmq --address amqp://user#pass:127.0.0.1:5672 --exchange events --routing-key \#
To watch all messages as they come in:
plumber read messages RabbitMQ --address amqp://user#pass:127.0.0.1:5672 --exchange events --routing-key \# --follow
If you use plumber your queue must be set up on its own exchange you can not use the RabbitMQ default exchange see.
i have to create a virtual topology with miniedit that has to talk using the mqtt sub/pub system.
i'm working on virtualbox (mininet-wifi)
i have installed mosquitto & the clients... using the terminals i have no problem with:
mosquitto_sub -t test
mosquitto_pub -t test -m hello!
but when i emulate the topology on Miniedit with (controller,switch and two hosts), the hosts cannot talk using mosquitto, i think that there is no broker that can handle the communications in the virtual topology, any suggestions?
I tried to connect also to a remote server, using cloudmqtt but i only got failed connection
i expect that using
xterm h1 h2
on the Comand Line Interface of miniedit, i would be capable of make the two hosts talks beetween them using
mosquitto_sub/pub system, because also in the xterm of the host, if i type
service mosquitto status
i obtain that
mosquitto is active
UPDATE
solved.
i just have to run another host in which i type "mosquitto" and the others hosts would just reach it using "mosquitto_sub/pub - h 10.0.0.3 for example
2 brokers (1 on each hosts) won't automatically discover each other when the "link" comes up.
You will have to either manually configure the a bridge between the 2 brokers if you want messages to be shared.
Or pick one and have the clients explicitly connect to that one broker. e.g. the -h option for the mosquitto_pub or mosquitto_sub commands.
I agree with the solution. Let me give more in depth explanation.
Run basic mininet topo with 4 hosts and 4 switches.
mn --topo linear,4
Then open xterm for 3 hosts
xterm h1 h2 h3
Three terminals will pop up. One of them will be the host. on h3's(10.0.0.3) xterm terminal run
mosquitto
On h2(10.0.0.2) subscribe to the topic with;
mosquitto_sub -h 10.0.0.3 -t "home/bedroom/light"
On h1(10.0.0.1) publish a message by;
mosquitto_pub -h 10.0.0.3 -t "home/bedroom/light" -m "ON"
You can now see the message on h2's terminal. Hope it helps.