How can I run a search job periodically in Azure Log Analytics? - azure

I'm trying to visualize the browser statistics of our app hosted in Azure.
For that I'm using the nginx logs and run an Azure Log Analytics query like this:
ContainerLog
| where LogEntrySource == "stdout" and LogEntry has "nginx"
| extend logEntry=parse_json(LogEntry)
| extend userAgent=parse_user_agent(logEntry.nginx.http_user_agent, "browser")
| extend browser=parse_json(userAgent)
| summarize count=count() by tostring(browser.Browser.Family)
| sort by ['count']
| render piechart with (legend=hidden)
Then I'm getting this diagram, which is exactly what I want:
But the query is very very slow. If I set the time range to more than just the last few hours it takes several minutes or doesn't work at all.
My solution is to use a search job like this:
ContainerLog
| where LogEntrySource == "stdout" and LogEntry has "nginx"
| extend d=parse_json(LogEntry)
| extend user_agent=parse_user_agent(d.nginx.http_user_agent, "browser")
| extend browser=parse_json(user_agent)
It creates a new table BrowserStats_SRCH on which I can do this search query:
BrowserStats_SRCH
| summarize count=count() by tostring(browser.Browser.Family)
| sort by ['count']
| render piechart with (legend=hidden)
This is much faster now and only takes some seconds.
But my problem is, how can I keep this up-to-date? Preferably this search job would run once a day automatically and refreshed the BrowserStats_SRCH table so that new queries on that table run always on the most recent logs. Is this possible? Right now I can't even trigger the search job manually again, because then I get the error "A destination table with this name already exists".
In the end I would like to have a deeplink to the pie chart with the browser stats without the need to do any further click. Any help would be appreciated.

But my problem is, how can I keep this up-to-date? Preferably this search job would run once a day automatically and refreshed the BrowserStats_SRCH table so that new queries on that table run always on the most recent logs. Is this possible?
You can leverage the api to create a search job. Then use a timer triggered azure function or logic app to call that api on a schedule.
PUT https://management.azure.com/subscriptions/00000000-0000-0000-0000-00000000000/resourcegroups/testRG/providers/Microsoft.OperationalInsights/workspaces/testWS/tables/Syslog_suspected_SRCH?api-version=2021-12-01-preview
with a request body containing the query
{
"properties": {
"searchResults": {
"query": "Syslog | where * has 'suspected.exe'",
"limit": 1000,
"startSearchTime": "2020-01-01T00:00:00Z",
"endSearchTime": "2020-01-31T00:00:00Z"
}
}
}
Or you can use the Azure CLI:
az monitor log-analytics workspace table search-job create --subscription ContosoSID --resource-group ContosoRG --workspace-name ContosoWorkspace --name HeartbeatByIp_SRCH --search-query 'Heartbeat | where ComputerIP has "00.000.00.000"' --limit 1500 --start-search-time "2022-01-01T00:00:00.000Z" --end-search-time "2022-01-08T00:00:00.000Z" --no-wait
Right now I can't even trigger the search job manually again, because then I get the error "A destination table with this name already exists".
Before you start the job as described above, remove the old result table using an api call:
DELETE https://management.azure.com/subscriptions/{subscriptionId}/resourcegroups/{resourceGroupName}/providers/Microsoft.OperationalInsights/workspaces/{workspaceName}/tables/{tableName}?api-version=2021-12-01-preview
Optionally, you could check the status of the job using this api before you delete it to make sure it is not InProgress or Deleting

Related

Creating an alert for long running pipelines

I currently have an alert setup for Data Factory that sends an email alert if the pipeline runs longer than 120 minutes, following this tutorial: https://www.techtalkcorner.com/long-running-azure-data-factory-pipelines/. So when a pipeline does in fact run longer than the expected time, I do receive an alert however, I am also getting additional & unexpected alerts.
My query looks like:
ADFPipelineRun
| where Status =="InProgress" // Pipeline is in progress
| where RunId !in (( ADFPipelineRun | where Status in ("Succeeded","Failed","Cancelled") | project RunId ) ) // Subquery, pipeline hasn't finished
| where datetime_diff('minute', now(), Start) > 120 // It has been running for more than 120 minutes
I received an alert email on September 28th of course saying a pipeline was running longer than the 120 minutes but when trying to find the pipeline in the Azure Data Factory pipeline runs nothing shows up. In the alert email there is a button that says, "View the alert in Azure monitor" and when I go to that I can then press "View Query Results" above the shown query. Here I can re-enter the query above and filter the date to show all pipelines running longer than 120 minutes since September 27th and it returns 3 pipelines.
Something I noticed about these pipelines is the end time column:
I'm thinking that at some point the UTC time is not properly configured and for that reason, maybe the alert is triggered? Is there something I am doing wrong, or a better way to do this to avoid a bunch of false alarms?
To create Preemptive warnings for long-running jobs.
Create activity.
Click on blank space.
Follow path: Settings > Elapsed time metric
Refer Operationalize Data Pipelines - Azure Data Factory
I'm not sure if you're seeing false alerts. What you've shown here looks like the correct behavior.
You need to keep in mind:
Duration threshold should be offset by the time it takes for the logs to appear in Azure Monitor.
The email alert takes you to the query that triggered the event. Your query is only showing "InProgress" statues and so the End property is not set/updated. You'll need to extend your query to look at one of the other statues to see the actual duration.
Run another query with the RunId of the suspect runs to inspect the durations.
ADFPipelineRun
| where RunId == 'bf461c8b-0b1e-43c4-9cdf-7d9f7ccc6f06'
| distinct TimeGenerated, OperationName, RunId, Start, End, Status
For example:

Transcribing Splunk's "transaction" Command into Azure Log Analytics / Azure Data Analytics / Kusto

We're using AKS and have our container logs writing to Log Analytics. We have an application that emits several print statements in the container log per request, and we'd like to group all of those events/log lines into aggregate events, one event per incoming request, so it's easier for us to find lines of interest. So, for example, if the request started with the line "GET /my/app" and then later the application printed something about an access check, we want to be able to search through all the log lines for that request with something like | where LogEntry contains "GET /my/app" and LogEntry contains "access_check".
I'm used to queries with Splunk. Over there, this type of inquiry would be a cinch to handle with the transaction command:
But, with Log Analytics, it seems like multiple commands are needed to pull this off. Seems like I need to use extend with row_window_session in order to give all the related log lines a common timestamp, then summarize with make_list to group the lines of log output together into a JSON blob, then finally parse_json and strcat_array to assemble the lines into a newline-separated string.
Something like this:
ContainerLog
| sort by TimeGenerated asc
| extend RequestStarted= row_window_session(TimeGenerated, 30s, 2s, ContainerID != prev(ContainerID))
| summarize logLines = make_list(LogEntry) by RequestStarted
| extend parsedLogLines = strcat_array(parse_json(logLines), "\n")
| where parsedLogLines contains "GET /my/app" and parsedLogLines contains "access_check"
| project Timestamp=RequestStarted, LogEntry=parsedLogLines
Is there a better/faster/more straightforward way to be able to group multiple lines for the same request together into one event and then perform a search across the contents of that event?
After reading your question, there is no such an easy way to do that in azure log analytics.
If the logs are in this format, you need to do some other work to meet your requirement.

Get list of blob names for failed requests in Azure Monitor log query

There is a blob trigger function failing, which some are caused by a System.NullReferenceException. Is it possible to get the list of blob names that are causing this exception? What would that log query look like? Here is the query I have so far, but not sure where to go from here to get the list of blob names causing the Null Reference Exceptions.
requests
| where success == false
First, you should query from the dependencies table instead of requests table.
Then to get failed blob list, you can use the query like below:
dependencies
| where timestamp >ago(7d) // here the time range is set to the latest 7 days, you can change it.
| where success == "false"
| where type == "Azure blob"
| project customDimensions.Blob

Azure Log Analytics - Alerts Advice

I have a question about azure log analytics alerts, in that I don't quite understand how the time frame works within the context of setting up an alert based on an aggregated value.
I have the code below:
Event | where Source == "EventLog" and EventID == 6008 | project TimeGenerated, Computer | summarize AggregatedValue = count(TimeGenerated) by Computer, bin_at(TimeGenerated,24h, datetime(now()))
For time window : 24/03/2019, 09:46:29 - 25/03/2019, 09:46:29
In the above the alert configuration interface insights on adding the bin_at(TimeGenerated,24h, datetime(now())) so I add the function, passing the arguments for a 24h time period. If you are already adding this then what is the point of the time frame.
Basically the result I am looking for is capturing this event over a 24 hour period and alerting when the event count is over 2. I don't understand why a time window is also necessary on top of this because I just want to run the code every five minutes and alert if it detects more than two instances of this event.
Can anyone help with this?
AFAIK you may use the query something like shown below to accomplish your requirement of capturing the required event over a time period of 24 hour.
Event
| where Source == "EventLog" and EventID == 6008
| where TimeGenerated > ago(24h)
| summarize AggregatedValue= any(EventID) by Computer, bin(TimeGenerated, 1s)
The '1s' in this sample query is the time frame with which we are aggregating and getting the output from Log Analytics workspace repository. For more information, refer https://learn.microsoft.com/en-us/azure/kusto/query/summarizeoperator
And to create an alert, you may have to go to Azure portal -> YOURLOGANALYTICSWORKSPACE -> Monitoring tile -> Alerts -> Manager alert rules -> New alert rule -> Add condition -> Custom log search -> Paste any of the above queries under 'Search query' section -> Type '2' under 'Threshold value' parameter of 'Alert logic' section -> Click 'Done' -> Under 'Action Groups' section, select existing action group or create a new one as explained in the below mentioned article -> Update 'Alert Details' -> Click on 'Create alert rule'.
https://learn.microsoft.com/en-us/azure/azure-monitor/platform/action-groups
Hope this helps!! Cheers!! :)
To answer your question in the comments part, yes the alert insists on adding the bin function and that's the reason I have provided relevant query along with bin function by having '1s' and tried to explain about it in my previous answer.
If you put '1s' in bin function then you would fetch output from Log Analytics by aggregating value of any EventID in the timespan of 1second. So output would look something like shown below where aaaaaaa is considered as a VM name, x is considered as a particular time.
If you put '24h' instead of '1s' in bin function then you would fetch output from Log Analytics by aggregating value of any EventID in the timespan of 24hours. So output would look something like shown below where aaaaaaa is considered as a VM name, x is considered as a particular time.
So in this case, we should not be using '24h' in bin function along with 'any' aggregation because if we use it then we would see only one occurrence of output in 24hours of timespan and that doesn't help you to find out event occurrence count using the above provided query having 'any' for aggregation. Instead you may use 'count' aggregation instead of 'any' if you want to have '24h' in bin function. Then this query would look something like shown below.
Event
| where Source == "EventLog" and EventID == 6008
| where TimeGenerated > ago(24h)
| summarize AggregatedValue= count(EventID) by Computer, bin(TimeGenerated, 24h)
The output of this query would look something like shown below where aaaaaaa is considered as a VM name, x is considered as a particular time, y and z are considered as some numbers.
One other note is, all the above mentioned queries and outputs are in the context of setting up an alert based on an aggregated value i.e., setting up an alert when opting 'metric measurement' under alert logic based on section. In other words, aggregatedvalue column is expected in alert query when you opt 'metric measurement' under alert logic based on section. But when you say 'you get a count of the events' that means If i am not wrong, may be you are opting 'number of results' under alert logic based on section, which would not required any aggregation column in the query.
Hope this clarifies!! Cheers!!

Filter data from CustomEvent

I have data in azure Insights saved in custom events formats.
Now I need to create a dashboard page in my website that will pull data from insights and will show graphs on that data.
Questions is that how I can filter data from the customEvents based on data saved there. like based on custom events or custom data.
Provide me any resource from where I can see that how $filer, $search,$query works?
I am here https://dev.applicationinsights.io/quickstart but not looks like enough.
I tried to add filter like
startswith(customEvent/name, 'BotMessageReceived')
in https://dev.applicationinsights.io/apiexplorer/events
but it not working. is says "Something went wrong while running the query",
I have customEvents which name start with BotMessageReceived
Thanks
Dalvir
update:
There is no like operator, if you wanna use timestamp as a filter, you should use one of the three methods below:
customEvents
| where timestamp >= datetime('2018-11-23T00:00:00.000') and timestamp <=
datetime('2018-11-23T23:59:00.000')
customEvents
| where tostring(timestamp) contains "2018-12-11"
customEvents
| where timestamp between(datetime('2018-11-23T00:00:00.000') ..
datetime('2018-11-23T23:59:00.000') )
Please use this:
customEvents
| where name startswith "BotMessageReceived"
And if you use the api you metioned above, you can use:
https://api.applicationinsights.io/v1/apps/Your_application_id/query?
query=customEvents | where name startswith "BotMessageReceived"
It works at my side.

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