Re: Howto change log level with Solr Admin UI ?

[Shawn Heisey]

On 4/19/2018 12:32 AM, Bernd Fehling wrote:

Would be cool if that would be possible, to change the log level for solr.log
from the Admin UI. Imagine, a running system with problems, you can change
log level and get more logging info into solr.log without restarting the system
and overloading the Logging Admin UI:


That's exactly what the logging level page is for.

With a default configuration, any entry that you change, to any level, 
has the potential to affect what is logged to solr.log.  If you set an 
entry to a level that's higher than WARN, it has the potential to affect 
both solr.log as well as reduce logging seen in the admin UI.  Whether 
or not a particular change has any noticeable effect will depend on 
exactly what logging statements are in the the affected class(es) and 
exactly what Solr is doing.


For an example that should make a visible change to solr.log on a server 
that's actively being used, find in the structure 
org->apache->solr->handler and set that to DEBUG.  When I did this on a 
6.x version, each query that Solr received logged an extra line, 
duplicating much of the information already being logged at INFO.  To 
remove the change, set it to UNSET.


Thanks,
Shawn

Re: Howto change log level with Solr Admin UI ?

[Bernd Fehling]

Hi Emir,
thanks for the infos, it works for the Admin UI.
But it fills the Admin UI pretty heavy with log messages.

I think it is a misunderstanding on my side because I was hoping to change
the log level for solr.log with Admin UI.
Would be cool if that would be possible, to change the log level for solr.log
from the Admin UI. Imagine, a running system with problems, you can change
log level and get more logging info into solr.log without restarting the system
and overloading the Logging Admin UI:

In my C and C++ programs I use SIGUSR1 and SIGUSR2 to change log levels during 
runtime.

Regards
Bernd


Am 18.04.2018 um 17:18 schrieb Emir Arnautović:
> Hi,
> It is not exposed in the admin console (would be nice if it is!), but there 
> is a way to set threshold for admin UI logs. You can simply execute 
> following:  
> http://localhost:8983/solr/admin/info/logging?since=0=INFO 
>  and 
> INFO logs will start appearing in admin UI.
> 
> HTH,
> Emir
> --
> Monitoring - Log Management - Alerting - Anomaly Detection
> Solr & Elasticsearch Consulting Support Training - http://sematext.com/
> 
> 
> 
>> On 18 Apr 2018, at 16:30, Shawn Heisey  wrote:
>>
>> On 4/18/2018 8:03 AM, Bernd Fehling wrote:
>>> I just tried to change the log level with Solr Admin UI but it
>>> does not change any logging on my running SolrCloud.
>>> It just shows the changes in the Admin UI and the commands in the
>>> request log, but no changes in the level of logging.
>>>
>>> Do I have to RELOAD the collection after changing log level?
>>>
>>> I tried all setting from ALL, TRACE, DEBUG, ...
>>>
>>> Also the Reference Guide 6.6 shows the Admin UI as I see it, but
>>> the table below the image has levels FINEST, FINE, CONFIG, ...
>>> https://lucene.apache.org/solr/guide/6_6/configuring-logging.html
>>> This is confusing.
>>
>> What exact setting in the logging tab did you change, and what did you 
>> expect to happen that didn't happen?
>>
>> The logging events that show up in the admin UI will never include anything 
>> with a severity lower than WARN.  Anything lower would be far too much 
>> information for the admin UI to handle.  Changing the level shown in the 
>> admin UI is likely possible, but probably requires a code change.  If 
>> changed, I think it would result in a UI page that's unusable because it 
>> contains far too many events.
>>
>> Assuming that log4j.properties hasn't been altered, you will find lower 
>> severity events in solr.log, a file on disk.  The default logging level that 
>> Solr uses is INFO, but INFO logs never show up in the admin UI.
>>
>> Also, changes made to logging levels in the admin UI only last as long as 
>> Solr is running.  When Solr is restarted, those changes are gone.  Only 
>> changes made in log4j.properties will survive a restart.
>>
>> Thanks,
>> Shawn
>>
> 
> 

Re: Howto change log level with Solr Admin UI ?

[Shalin Shekhar Mangar]

The changes made using the admin logging UI are local to the node. It will
not change logging settings on other nodes and these changes do not persist
between restarts.

On Wed, Apr 18, 2018 at 7:33 PM, Bernd Fehling <
bernd.fehl...@uni-bielefeld.de> wrote:

> I just tried to change the log level with Solr Admin UI but it
> does not change any logging on my running SolrCloud.
> It just shows the changes in the Admin UI and the commands in the
> request log, but no changes in the level of logging.
>
> Do I have to RELOAD the collection after changing log level?
>
> I tried all setting from ALL, TRACE, DEBUG, ...
>
> Also the Reference Guide 6.6 shows the Admin UI as I see it, but
> the table below the image has levels FINEST, FINE, CONFIG, ...
> https://lucene.apache.org/solr/guide/6_6/configuring-logging.html
> This is confusing.
>
>
> Regards,
> Bernd
>



-- 
Regards,
Shalin Shekhar Mangar.

Re: Howto change log level with Solr Admin UI ?

[Emir Arnautović]

Hi,
It is not exposed in the admin console (would be nice if it is!), but there is 
a way to set threshold for admin UI logs. You can simply execute following:  
http://localhost:8983/solr/admin/info/logging?since=0=INFO 
 and INFO 
logs will start appearing in admin UI.

HTH,
Emir
--
Monitoring - Log Management - Alerting - Anomaly Detection
Solr & Elasticsearch Consulting Support Training - http://sematext.com/



> On 18 Apr 2018, at 16:30, Shawn Heisey  wrote:
> 
> On 4/18/2018 8:03 AM, Bernd Fehling wrote:
>> I just tried to change the log level with Solr Admin UI but it
>> does not change any logging on my running SolrCloud.
>> It just shows the changes in the Admin UI and the commands in the
>> request log, but no changes in the level of logging.
>> 
>> Do I have to RELOAD the collection after changing log level?
>> 
>> I tried all setting from ALL, TRACE, DEBUG, ...
>> 
>> Also the Reference Guide 6.6 shows the Admin UI as I see it, but
>> the table below the image has levels FINEST, FINE, CONFIG, ...
>> https://lucene.apache.org/solr/guide/6_6/configuring-logging.html
>> This is confusing.
> 
> What exact setting in the logging tab did you change, and what did you expect 
> to happen that didn't happen?
> 
> The logging events that show up in the admin UI will never include anything 
> with a severity lower than WARN.  Anything lower would be far too much 
> information for the admin UI to handle.  Changing the level shown in the 
> admin UI is likely possible, but probably requires a code change.  If 
> changed, I think it would result in a UI page that's unusable because it 
> contains far too many events.
> 
> Assuming that log4j.properties hasn't been altered, you will find lower 
> severity events in solr.log, a file on disk.  The default logging level that 
> Solr uses is INFO, but INFO logs never show up in the admin UI.
> 
> Also, changes made to logging levels in the admin UI only last as long as 
> Solr is running.  When Solr is restarted, those changes are gone.  Only 
> changes made in log4j.properties will survive a restart.
> 
> Thanks,
> Shawn
> 

Re: Howto change log level with Solr Admin UI ?

[Shawn Heisey]

On 4/18/2018 8:03 AM, Bernd Fehling wrote:

I just tried to change the log level with Solr Admin UI but it
does not change any logging on my running SolrCloud.
It just shows the changes in the Admin UI and the commands in the
request log, but no changes in the level of logging.

Do I have to RELOAD the collection after changing log level?

I tried all setting from ALL, TRACE, DEBUG, ...

Also the Reference Guide 6.6 shows the Admin UI as I see it, but
the table below the image has levels FINEST, FINE, CONFIG, ...
https://lucene.apache.org/solr/guide/6_6/configuring-logging.html
This is confusing.


What exact setting in the logging tab did you change, and what did you 
expect to happen that didn't happen?


The logging events that show up in the admin UI will never include 
anything with a severity lower than WARN.  Anything lower would be far 
too much information for the admin UI to handle.  Changing the level 
shown in the admin UI is likely possible, but probably requires a code 
change.  If changed, I think it would result in a UI page that's 
unusable because it contains far too many events.


Assuming that log4j.properties hasn't been altered, you will find lower 
severity events in solr.log, a file on disk.  The default logging level 
that Solr uses is INFO, but INFO logs never show up in the admin UI.


Also, changes made to logging levels in the admin UI only last as long 
as Solr is running.  When Solr is restarted, those changes are gone.  
Only changes made in log4j.properties will survive a restart.


Thanks,
Shawn

Howto change log level with Solr Admin UI ?

[Bernd Fehling]

I just tried to change the log level with Solr Admin UI but it
does not change any logging on my running SolrCloud.
It just shows the changes in the Admin UI and the commands in the
request log, but no changes in the level of logging.

Do I have to RELOAD the collection after changing log level?

I tried all setting from ALL, TRACE, DEBUG, ...

Also the Reference Guide 6.6 shows the Admin UI as I see it, but
the table below the image has levels FINEST, FINE, CONFIG, ...
https://lucene.apache.org/solr/guide/6_6/configuring-logging.html
This is confusing.


Regards,
Bernd