Handling pycassa.pool.AllServersUnavailable exception. Response to http://stackoverflow.com/questions/15906550/how-to-handle-allserversunavailable-exception

choke.py

import pycassa
import time
import string
from pycassa.pool import ConnectionPool
from pycassa.columnfamily import ColumnFamily
import uuid
import random
import sys

pool = ConnectionPool('testdb')
test_cf = ColumnFamily(pool,'test')
test2_cf = ColumnFamily(pool,'test2')
test3_cf = ColumnFamily(pool,'test3')
test_batch = test_cf.batch(queue_size=1000)
test2_batch = test2_cf.batch(queue_size=1000)
test3_batch = test3_cf.batch(queue_size=1000)

chars=string.ascii_uppercase
counter = 0
while True:
    counter += 1
    uid = uuid.uuid1()
    junk = ''.join(random.choice(chars) for x in range(50))
    tryCount = 5  # 5 is probably unnecessarily high
    while tryCount > 0:
      try:
        test_batch.insert(uid, {'junk':junk})
        test2_batch.insert(uid, {'junk':junk})
        test3_batch.insert(uid, {'junk':junk})
        tryCount = -1
      except pycassa.pool.AllServersUnavailable as e:
        print "Trying to insert [" + str(uid) + "] but got error " + str(e) + " (attempt " + str(tryCount) + "). Backing off for a minute to let Cassandra settle down"
        time.sleep(60) # A delay of 60s is probably unnecessarily high
        tryCount = tryCount - 1
    sys.stdout.write(str(counter)+'\n')

pool.dispose()

testdb.cli

use testdb;
create column family test and key_validation_class = 'UUIDType';
create column family test2 and key_validation_class = 'UUIDType';
create column family test3 and key_validation_class = 'UUIDType';