Internal error: TimedOutException: Default TException

HI
Good day,

I'm copying a table with 10000 of lines, containing a field that is blob, containing images, .pdf, and other files from Mysql 5.5 to a MariaDB 10.0.34 database, whose table is in Cassandra, and is accessed via "Cassandra storage engine ".
With great difficulty, I was able to insert a good part of the records of this table into Cassandra.
However, I am getting the following error messages when trying to count the records, or even just display the key field.

MariaDB [medicina_intramed]> select id from tbl_paciente_crm_anexo;
ERROR 1815 (HY000): Internal error: TimedOutException: Default TException.

MariaDB [medicina_intramed]> select count(id) from tbl_paciente_crm_anexo;
ERROR 1815 (HY000): Internal error: UnavailableException: Default TException.
MariaDB [medicina_intramed]>

When I search in Cassandra, accessing the same table, I get the following message:

cqlsh:md_paciente> select count(id) from cf_crm_anexo;
OperationTimedOut: errors=

, last_host=127.0.0.1
cqlsh:md_paciente>

Although the table has many blob fields, the critical field is the "file" field.
I have a lot of experience with relational databases, but I'm starting in the NOSQL environment.
And this is the my first project using Cassandra.
May be the a problem with parameters, but I was try many options without soluction.
I will have many apreciation by your support.

Best regards,