Uninstall Falcon

[#1]

Given the 503 error we are getting when trying to open the Falcon Web UI, our support engineer has recommended that we uninstall and reinstall falcon.

So I did a bit of research and found this command :

curl -u $USER:$PASS -i -H 'X-Requested-By: ambari'-X DELETE  http://$AMBARI_HOST:$AMBARI_PORT/api/v1/clusters/<cluster-name>/services/<service-name>;

So the $AMBARI_HOST in above command is the host on which Ambari is running - and not the host Falcon is running?

And what is the $AMBARI_PORT/port number to be used in the above command - 8080?

The USER/PASS is root and its password or falcon and its password? (I had done the HDP/Ambari installation as root).

Appreciate the clarification.

[#2 · Accepted solution]

• Yes $AMBARI_HOST is the ambari server host
• $AMBARI_PORT is the port you use for logging into Ambari by default 8080, unless you are using Wire encryption, for that case it will be 8443
• The USER/PASS are the ones you use to logon to ambari, generally the 'admin' user and its password.

[#3]

Thanks for the response. And BTW how to reinstall Falcon? Appreciate the feedback.

[#4]

You can follow doc to Install Falcon using Ambari UI or through the command line:

https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.5.3/bk_data-movement-and-integration/content/ch...

[#5]

@n c - Can you please upvote and accept the answer, if it resolved your issue. Thanks

[#6]

Is there any more help needed here. Thanks

[#7]

Non related to your question, but is your 503 issue related to:

https://community.hortonworks.com/articles/76537/falcon-web-ui-is-inaccessiblehttp-503-error-and-am....

Depending of the HDP version you have, an external dependency must be downloaded from the internet to get Falcon UI working.

[#8]

Yes I did check that but the said jar file is already available in our installation. Thanks

[#9]

Our vendor asked us to use this for removing falcon :

https://cwiki.apache.org/confluence/display/AMBARI/Using+APIs+to+delete+a+service+or+all+host+compon...

But the path given in the first command itself I cannot find in my installation :

http://AMBARI_SERVER_HOST:8080/api/v1/clusters/c1/services/SERVICENAME

Is the above path local to the installation given in the example?

By "SERVICE" I am equating with falcon as that is the service I am trying to remove.

When I searched for falcon in the Ambari host I got a bunch of directories - but substituting any of the directories in the above command only got me :

{ "status": 404, "message": "Not Found" }

[#10]

@n c

If you are accessing the URL: http://AMBARI_SERVER_HOST:8080/api/v1/clusters/c1/services/FALCON

And getting 404 which means FALCON service is not installed on your cluster.

You can list all the services that are installed on the cluster as following: http://AMBARI_SERVER_HOST:8080/api/v1/clusters/c1/services

[#11]

When I ran your command got this :

{
  "status": 403,
  "message": "Full authentication is required to access this resource"
}

[#12]

@n c

While using web browser, You will need to open the http://AMBARI_SERVER_HOST:8080 URL first in the browser then it will ask for username or password . One you are authenticated then you can open the previously mentioned URL. http://AMBARI_SERVER_HOST:8080/api/v1/clusters/c1/services

If you are using Curl or wget then you can simply use the following:

curl -u $USER:$PASS -i -H 'X-Requested-By: ambari'  -X GET http://AMBARI_SERVER_HOST:8080/api/v1/clusters/c1/services

.

[#13]

Thanks. I was missing the cluster name in the command. Thanks again.

[#14]

Hi @n c - Can you please post the exact command you are trying and any stack trace / screenshots for your issue.

Also, when you logon to Ambari, can see Falcon as a service on the Ambari UI.

[#15]

As mentioned by Namit, do be sure to follow the Prerequisite instructions under https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.5.3/bk_data-movement-and-integration/content/ch... before reinstalling. If you encounter any issues with these instructions, please let me know.