question Re: How to resolve Pig view errors on kerbereized cluster? in Archives of Support Questions (Read Only)

How to resolve Pig view errors on kerbereized cluster?

kabadou_rawia — Wed, 22 Nov 2017 00:44:11 GMT

Hello,

I need to test a script through Pig View on my kerbereized cluster.

I attached my script details in script.png.

When i run this script i got the error mentioned in error.png through /var/log/ambari-server/pig-view/pig-view.log.

I access to Ambari UI with admin as username.

How can i resolve this issue?

I'll be really grateful if someone could help me.

Re: How to resolve Pig view errors on kerbereized cluster?

jsensharma — Wed, 22 Nov 2017 02:23:14 GMT

@raouia

- Which version of ambari are you using? There is a "auth" property which is only needed if the view is Custom Configured or Ambari Server is Kerberized before 2.4.0.

- If you are using prior version of ambari then can you please check if you have set the ambari-server principal to your pig view for auth? You can refer to the following doc to get more detailed information about it: https://docs.hortonworks.com/HDPDocuments/Ambari-2.6.0.0/bk_ambari-views/content/section_pig_view_kerberos_config.html

auth=KERBEROS;proxyuser=<ambari-principal-name>

You can find the ambariserver principal name inside the following file "/etc/ambari-server/conf/krb5JAASLogin.conf"

Example:

# cat /etc/ambari-server/conf/krb5JAASLogin.conf
com.sun.security.jgss.krb5.initiate {
        com.sun.security.auth.module.Krb5LoginModule required
        renewTGT=false
        doNotPrompt=true
        useKeyTab=true
        keyTab="/etc/security/keytabs/ambari.server.keytab"
        principal="ambari-server-kerberos_ambari@EXAMPLE.COM"
        storeKey=true
        useTicketCache=false;
    };

Also please check if you have configured the "hadoop.proxyuser" property set properly for the "HDFS" and "WebHCAT" as described in the following doc: https://docs.hortonworks.com/HDPDocuments/Ambari-2.6.0.0/bk_ambari-views/content/configuring_your_cluster_for_pig_view.html

Re: How to resolve Pig view errors on kerbereized cluster?

kabadou_rawia — Wed, 22 Nov 2017 16:39:48 GMT

@Jay Kumar SenSharma

Thank you very much for your reply.

- My ambari version is Version 2.5.1.0.

- My ambari server is running with root user. So,i resecured my cluster with the principal "root@ROSAFI.COM" and made all the necessary configurations by following this link:

https://docs.hortonworks.com/HDPDocuments/Ambari-2.4.1.0/bk_ambari-security/content/set_up_kerberos_for_ambari_server.html.

The output of file "/etc/ambari-server/conf/krb5JAASLogin.conf" is:

com.sun.security.jgss.krb5.initiate {
    com.sun.security.auth.module.Krb5LoginModule required
    renewTGT=false
    doNotPrompt=true
    useKeyTab=true
    keyTab="/etc/security/keytabs/root.server.keytab"
    principal="root@ROSAFI.COM"
    storeKey=true
    useTicketCache=false;
};

- I've also made the necessary configuration in Pig view as mentioned in pig-auth.png.

- I've set "hadoop.proxyuser" in HDFS as shown in proxyuser.png.

I'm really stuck. Please help me understanding the cause of this issue.

Re: How to resolve Pig view errors on kerbereized cluster?

jsensharma — Wed, 22 Nov 2017 17:41:30 GMT

@raouia

Based on your "/etc/ambari-server/conf/krb5JAASLogin.conf" file setting "principal" we see that your ambari server principal name is "root@ROSAFI.COM" hence your PigView Auth setting should be something like following, Which is correctly set in your case.

auth=KERBEROS;proxyuser=root

.
But we noticed the following error inside your "error.png" image saying that

org.apache.ambari.view.utils.ambari.AmbariApiException: {"error":"User: HTTP/ambari@ROSAFI.COM is not allowed to impersonate admin"}

Suggestion:
Which indicates that you have not set the following property properly inside the hadoop core-site.xml inside the proxyuser settings:

hadoop.proxyuser.HTTP.hosts=*
hadoop.proxyuser.HTTP.group=*

So can you please try adding the above two properties and then try again. Also please do a kinit as following isnide ambari server host and then restart ambari-server once.

# kdestroy
# kinit -kt /etc/security/keytabs/root.server.keytab  root@ROSAFI.COM
# klist
# ambari-server stop
# ambari-server start

Then try to access the ambari UI again.

Re: How to resolve Pig view errors on kerbereized cluster?

kabadou_rawia — Wed, 22 Nov 2017 18:30:05 GMT

@Jay Kumar SenSharma

Thank you very much. Your suggestion worked for me.