question Re: No available Impalad to send queries to in Support Questions

No available Impalad to send queries to

MC — Fri, 16 Sep 2022 09:29:08 GMT

We are running CDH 5.3.3 with Hue 3.7.0, and just added impala via Cloudera Manager. Whenever we log on to Hue, the "No available Impalad to send queries to." appears. Cloudera Manager doesn't report anything wrong with either impala or Hue. The impala and Hue logs don't show any errors.

Any help would be greatly appreciated.

Thanks!

For completeness, I also want to add that the impala-shell works without a problem. The issue seems to be restricted to Hue.

Re: No available Impalad to send queries to

Romainr — Fri, 15 May 2015 16:13:49 GMT

Are all the impalads up in the Impala service? (in the "instances" tab)

Romain

Re: No available Impalad to send queries to

MC — Fri, 15 May 2015 16:17:49 GMT

Yes, they are. Cloudera Manager doesn't report any anomaly, and nothing is shown in the logs that might indicate a problem of any nature. Impala-shell works fine. Hue is the only thing that seems to have issues. Server name and port number for impala in hue.ini are correct. The deamon on the target host is indeed listening to the right port number.

Re: No available Impalad to send queries to

Romainr — Fri, 15 May 2015 16:22:49 GMT

Is the Hue Impala App working or do you just get the warning on the
start-up page?

Did you also check the impalad address on the Hue page /desktop/dump_config
[impala] tab?

Romain

Re: No available Impalad to send queries to

MC — Fri, 15 May 2015 16:35:49 GMT

I get the message right after I log on to Hue, right at the time Hue checks the configuration. As for the app, if I click on it, the browser hangs for a while before finally showing the Impala editor page. However, no list of databases is shown as the app seems unable to retrieve any.

Re: No available Impalad to send queries to

Romainr — Fri, 15 May 2015 16:39:49 GMT

Did you check the /desktop/check_config page?

Re: No available Impalad to send queries to

MC — Fri, 15 May 2015 16:52:49 GMT

I'm sorry, bear with me. On the configuration page for Hue, if I click on "desktop" in the "Configuration Sections and Variables" section I don't see check_config. Am I looking in the wrong place?

Re: No available Impalad to send queries to

MC — Fri, 15 May 2015 17:09:41 GMT

Unless you are talking about the Hue main page. Here is a snapshot that shows what I see after logging on to Hue:

Re: No available Impalad to send queries to

Romainr — Fri, 15 May 2015 17:14:49 GMT

For some reason I don't see the picture 😉

But if you go http://hue-host:8888/desktop/dump_config --> "Configuration
Sections and Variables" --> [impala]

Check server_host and server_port

Romain

Re: No available Impalad to send queries to

MC — Fri, 15 May 2015 17:25:49 GMT

Thanks. Server_name is one of the servers where the impalad deamon is running. The port number is the default one (21050).

Re: No available Impalad to send queries to

Romainr — Fri, 15 May 2015 17:35:49 GMT

Could you use the impala shell to connect to the impalad and give a try?

How about restarting just this impalad?

Re: No available Impalad to send queries to

MC — Fri, 15 May 2015 17:39:49 GMT

As I mentioned earlier, the impala shell works fine. I can connect and work with Impala without any problems.

Re: No available Impalad to send queries to

Romainr — Fri, 15 May 2015 17:42:49 GMT

But do you connect to this exact same impalad?

Re: No available Impalad to send queries to

MC — Fri, 15 May 2015 17:46:49 GMT

Yes, I do.

Re: No available Impalad to send queries to

Romainr — Fri, 15 May 2015 17:49:49 GMT

So I don't know. You could share the /logs page content after opening the
editor. Then see if restarting Hue would unfreeze it

Re: No available Impalad to send queries to

MC — Fri, 15 May 2015 17:56:49 GMT

Let me run a full restart in case something is hosed somewhere. I'll update the post as soon as I'm done. Thanks for your help.

Re: No available Impalad to send queries to

MC — Sat, 16 May 2015 16:40:04 GMT

Problem solved. Rebooting the cluster servers didn’t fix the issue. The problem was due to Hue being configured with LDAP. Even though I didn’t find anything that says otherwise, I didn’t think that Having LDAP implemented for Hue required Impala too to be configured for LDAP. After doing that the misconfiguration message disappears, and everything works fine.

Thanks again for your help!

Re: No available Impalad to send queries to

cconner — Mon, 18 May 2015 13:29:49 GMT

Just curious, what ldap properties did you have set for Hue? Hue being configured for Ldap should not force Impala to require Ldap.

Re: No available Impalad to send queries to

MC — Mon, 18 May 2015 13:35:49 GMT

That's what I thought too. However, the problem disappeared only after setting the following properties via Cloudera Manager in the Impala Command Line Argument Advanced Configuration Snippet (Safety Valve):
-ldap_allow_anonymous_binds=false
-ldap_domain=
-ldap_manual_config=false
-ldap_passwords_in_clear_ok=true
-ldap_tls=false
-ldap_uri=
I know the option values for some of them are the default ones, but I chose to add the options to the Safety Valve anyway for completeness.

Re: No available Impalad to send queries to

cconner — Mon, 18 May 2015 13:42:10 GMT

Oh, sorry, meant which ldap properties did you have set for Hue? Mainly, did you have:

[desktop]
ldap_username=
ldap_password=