how do I get the connected drillbit's hostname or IP when using zookeeper?

[Mark Rajcok <mr...@gmail.com>]

I'm using a zookeeper connection string to get a connection to a drill
cluster. I would like to log which drillbit (hostname or IP address) I
successfully connected to, but I can't find any property or method on
the java.sql.Connection
class <https://docs.oracle.com/javase/8/docs/api/java/sql/Connection.html>
to get this information.

I tried connection.getMetaData.getURL, but that just returns the zookeeper
connection string I used to get the connection (scala code below):
import java.sql._
Class.forName("com.mapr.drill.jdbc41.Driver")
val con =
DriverManager.getConnection("jdbc:drill:zk=<server1>:5181,<server2>:5181/drill/<cluster_name>...")
con.getMetaData().getURL()  // returns "jdbc:drill:zk=<server1>...", so not
what I'm looking for
val st  = con.createStatement()
val res = st.executeQuery("select *,'findme' from sys.drillbits")
while(res.next()) { println(res.getString(1)) }

If I "grep" the drillbit_queries.json logs on all of the drillbit servers
for "findme", I can find which drillbit was used to execute the query, and
hence which drillbit I'm currently connected to. For tracking down
connection issues, however, I'd like to be able to log which drillbit is
being used from the application, rather than have to grep logfiles.

This question is also posted on StackOverflow:
https://stackoverflow.com/questions/68042577/how-to-determine-which-apache-drill-drillbit-was-selected-when-connecting-via-zo

Re: how do I get the connected drillbit's hostname or IP when using zookeeper?

[Ted Dunning <td...@apache.org>]

Mark,

That's a great trick to grep for a unique string in the query!

You don't have to grep logs, however, when you can grep the profiles or profiles_json system table for the same information. That grepping is simple enough to do in SQL, so you should be good to go.

On 2021/06/26 20:28:26, Mark Rajcok <mr...@gmail.com> wrote: 
> I'm using a zookeeper connection string to get a connection to a drill
> cluster. I would like to log which drillbit (hostname or IP address) I
> successfully connected to, but I can't find any property or method on
> the java.sql.Connection
> class <https://docs.oracle.com/javase/8/docs/api/java/sql/Connection.html>
> to get this information.
> 
> I tried connection.getMetaData.getURL, but that just returns the zookeeper
> connection string I used to get the connection (scala code below):
> import java.sql._
> Class.forName("com.mapr.drill.jdbc41.Driver")
> val con =
> DriverManager.getConnection("jdbc:drill:zk=<server1>:5181,<server2>:5181/drill/<cluster_name>...")
> con.getMetaData().getURL()  // returns "jdbc:drill:zk=<server1>...", so not
> what I'm looking for
> val st  = con.createStatement()
> val res = st.executeQuery("select *,'findme' from sys.drillbits")
> while(res.next()) { println(res.getString(1)) }
> 
> If I "grep" the drillbit_queries.json logs on all of the drillbit servers
> for "findme", I can find which drillbit was used to execute the query, and
> hence which drillbit I'm currently connected to. For tracking down
> connection issues, however, I'd like to be able to log which drillbit is
> being used from the application, rather than have to grep logfiles.
> 
> This question is also posted on StackOverflow:
> https://stackoverflow.com/questions/68042577/how-to-determine-which-apache-drill-drillbit-was-selected-when-connecting-via-zo
>