ClickHouse/tests/integration/test_dns_cache/test.py
2024-03-10 10:00:18 +01:00

320 lines
10 KiB
Python

import pytest
from helpers.client import QueryRuntimeException
from helpers.cluster import ClickHouseCluster
from helpers.test_tools import TSV
from helpers.test_tools import assert_eq_with_retry
cluster = ClickHouseCluster(__file__)
def _fill_nodes(nodes, table_name):
for node in nodes:
node.query(
"""
CREATE DATABASE IF NOT EXISTS test;
CREATE TABLE IF NOT EXISTS {0}(date Date, id UInt32)
ENGINE = ReplicatedMergeTree('/clickhouse/tables/test/{0}', '{1}')
ORDER BY id PARTITION BY toYYYYMM(date);
""".format(
table_name, node.name
)
)
node1 = cluster.add_instance(
"node1",
main_configs=["configs/listen_host.xml"],
with_zookeeper=True,
ipv6_address="2001:3984:3989::1:1111",
)
node2 = cluster.add_instance(
"node2",
main_configs=["configs/listen_host.xml", "configs/dns_update_long.xml"],
with_zookeeper=True,
ipv6_address="2001:3984:3989::1:1112",
)
@pytest.fixture(scope="module")
def cluster_without_dns_cache_update():
try:
cluster.start()
_fill_nodes([node1, node2], "test_table_drop")
yield cluster
except Exception as ex:
print(ex)
raise
finally:
cluster.shutdown()
pass
# node1 is a source, node2 downloads data
# node2 has long dns_cache_update_period, so dns cache update wouldn't work
def test_ip_change_drop_dns_cache(cluster_without_dns_cache_update):
# In this case we should manually set up the static DNS entries on the source host
# to exclude resplving addresses automatically added by docker.
# We use ipv6 for hosts, but resolved DNS entries may contain an unexpected ipv4 address.
node2.set_hosts([("2001:3984:3989::1:1111", "node1")])
# drop DNS cache
node2.query("SYSTEM DROP DNS CACHE")
node2.query("SYSTEM DROP CONNECTIONS CACHE")
# First we check, that normal replication works
node1.query(
"INSERT INTO test_table_drop VALUES ('2018-10-01', 1), ('2018-10-02', 2), ('2018-10-03', 3)"
)
assert node1.query("SELECT count(*) from test_table_drop") == "3\n"
assert_eq_with_retry(node2, "SELECT count(*) from test_table_drop", "3")
# We change source node ip
cluster.restart_instance_with_ip_change(node1, "2001:3984:3989::1:7777")
node2.set_hosts([("2001:3984:3989::1:7777", "node1")])
# Put some data to source node1
node1.query(
"INSERT INTO test_table_drop VALUES ('2018-10-01', 5), ('2018-10-02', 6), ('2018-10-03', 7)"
)
# Check that data is placed on node1
assert node1.query("SELECT count(*) from test_table_drop") == "6\n"
# Because of DNS cache dest node2 cannot download data from node1
with pytest.raises(Exception):
assert_eq_with_retry(node2, "SELECT count(*) from test_table_drop", "6")
# drop DNS cache
node2.query("SYSTEM DROP DNS CACHE")
node2.query("SYSTEM DROP CONNECTIONS CACHE")
# Data is downloaded
assert_eq_with_retry(node2, "SELECT count(*) from test_table_drop", "6")
# Just to be sure check one more time
node1.query("INSERT INTO test_table_drop VALUES ('2018-10-01', 8)")
assert node1.query("SELECT count(*) from test_table_drop") == "7\n"
assert_eq_with_retry(node2, "SELECT count(*) from test_table_drop", "7")
node3 = cluster.add_instance(
"node3",
main_configs=["configs/listen_host.xml"],
with_zookeeper=True,
ipv6_address="2001:3984:3989::1:1113",
)
node4 = cluster.add_instance(
"node4",
main_configs=[
"configs/remote_servers.xml",
"configs/listen_host.xml",
"configs/dns_update_short.xml",
],
with_zookeeper=True,
ipv6_address="2001:3984:3989::1:1114",
)
@pytest.fixture(scope="module")
def cluster_with_dns_cache_update():
try:
cluster.start()
_fill_nodes([node3, node4], "test_table_update")
yield cluster
except Exception as ex:
print(ex)
raise
finally:
cluster.shutdown()
pass
# node3 is a source, node4 downloads data
# node4 has short dns_cache_update_period, so testing update of dns cache
def test_ip_change_update_dns_cache(cluster_with_dns_cache_update):
# First we check, that normal replication works
node3.query(
"INSERT INTO test_table_update VALUES ('2018-10-01', 1), ('2018-10-02', 2), ('2018-10-03', 3)"
)
assert node3.query("SELECT count(*) from test_table_update") == "3\n"
assert_eq_with_retry(node4, "SELECT count(*) from test_table_update", "3")
# We change source node ip
cluster.restart_instance_with_ip_change(node3, "2001:3984:3989::1:8888")
# Put some data to source node3
node3.query(
"INSERT INTO test_table_update VALUES ('2018-10-01', 5), ('2018-10-02', 6), ('2018-10-03', 7)"
)
# Check that data is placed on node3
assert node3.query("SELECT count(*) from test_table_update") == "6\n"
curl_result = node4.exec_in_container(["bash", "-c", "curl -s 'node3:8123'"])
assert curl_result == "Ok.\n"
cat_resolv = node4.exec_in_container(["bash", "-c", "cat /etc/resolv.conf"])
print(("RESOLV {}".format(cat_resolv)))
assert_eq_with_retry(
node4, "SELECT * FROM remote('node3', 'system', 'one')", "0", sleep_time=0.5
)
# Because of DNS cache update, ip of node3 would be updated
assert_eq_with_retry(
node4, "SELECT count(*) from test_table_update", "6", sleep_time=3
)
# Just to be sure check one more time
node3.query("INSERT INTO test_table_update VALUES ('2018-10-01', 8)")
assert node3.query("SELECT count(*) from test_table_update") == "7\n"
assert_eq_with_retry(node4, "SELECT count(*) from test_table_update", "7")
def test_dns_cache_update(cluster_with_dns_cache_update):
node4.set_hosts([("127.255.255.255", "lost_host")])
with pytest.raises(QueryRuntimeException):
node4.query("SELECT * FROM remote('lost_host', 'system', 'one')")
node4.query(
"CREATE TABLE distributed_lost_host (dummy UInt8) ENGINE = Distributed(lost_host_cluster, 'system', 'one')"
)
with pytest.raises(QueryRuntimeException):
node4.query("SELECT * FROM distributed_lost_host")
node4.set_hosts([("127.0.0.1", "lost_host")])
# Wait a bit until dns cache will be updated
assert_eq_with_retry(
node4, "SELECT * FROM remote('lost_host', 'system', 'one')", "0"
)
assert_eq_with_retry(node4, "SELECT * FROM distributed_lost_host", "0")
assert TSV(
node4.query(
"SELECT DISTINCT host_name, host_address FROM system.clusters WHERE cluster='lost_host_cluster'"
)
) == TSV("lost_host\t127.0.0.1\n")
assert TSV(node4.query("SELECT hostName()")) == TSV("node4")
# Check SYSTEM DROP DNS CACHE on node5 and background cache update on node6
node5 = cluster.add_instance(
"node5",
main_configs=["configs/listen_host.xml", "configs/dns_update_long.xml"],
user_configs=["configs/users_with_hostname.xml"],
ipv6_address="2001:3984:3989::1:1115",
)
node6 = cluster.add_instance(
"node6",
main_configs=["configs/listen_host.xml", "configs/dns_update_short.xml"],
user_configs=["configs/users_with_hostname.xml"],
ipv6_address="2001:3984:3989::1:1116",
)
@pytest.mark.parametrize("node", [node5, node6])
def test_user_access_ip_change(cluster_with_dns_cache_update, node):
node_name = node.name
node_num = node.name[-1]
# getaddrinfo(...) may hang for a log time without this options
node.exec_in_container(
[
"bash",
"-c",
'echo -e "options timeout:1\noptions attempts:2" >> /etc/resolv.conf',
],
privileged=True,
user="root",
)
assert (
node3.query("SELECT * FROM remote('{}', 'system', 'one')".format(node_name))
== "0\n"
)
assert (
node4.query("SELECT * FROM remote('{}', 'system', 'one')".format(node_name))
== "0\n"
)
node.set_hosts(
[
("127.255.255.255", "node3"),
(f"2001:3984:3989::1:88{node_num}4", "unknown_host"),
],
)
cluster.restart_instance_with_ip_change(
node3, "2001:3984:3989::1:88{}3".format(node_num)
)
cluster.restart_instance_with_ip_change(
node4, "2001:3984:3989::1:88{}4".format(node_num)
)
with pytest.raises(QueryRuntimeException):
node3.query("SELECT * FROM remote('{}', 'system', 'one')".format(node_name))
with pytest.raises(QueryRuntimeException):
node4.query("SELECT * FROM remote('{}', 'system', 'one')".format(node_name))
# now wrong addresses are cached
node.set_hosts([])
retry_count = 60
if node_name == "node5":
# client is not allowed to connect, so execute it directly in container to send query from localhost
node.exec_in_container(
["bash", "-c", 'clickhouse client -q "SYSTEM DROP DNS CACHE"'],
privileged=True,
user="root",
)
node.exec_in_container(
["bash", "-c", 'clickhouse client -q "SYSTEM DROP CONNECTIONS CACHE"'],
privileged=True,
user="root",
)
retry_count = 1
assert_eq_with_retry(
node3,
"SELECT * FROM remote('{}', 'system', 'one')".format(node_name),
"0",
retry_count=retry_count,
sleep_time=1,
)
assert_eq_with_retry(
node4,
"SELECT * FROM remote('{}', 'system', 'one')".format(node_name),
"0",
retry_count=retry_count,
sleep_time=1,
)
def test_host_is_drop_from_cache_after_consecutive_failures(
cluster_with_dns_cache_update,
):
with pytest.raises(QueryRuntimeException):
node4.query(
"SELECT * FROM remote('InvalidHostThatDoesNotExist', 'system', 'one')"
)
# Note that the list of hosts in variable since lost_host will be there too (and it's dropped and added back)
# dns_update_short -> dns_max_consecutive_failures set to 6
assert node4.wait_for_log_line(
regexp="Code: 198. DB::NetException: Not found address of host: InvalidHostThatDoesNotExist.",
look_behind_lines=300,
)
assert node4.wait_for_log_line(
"Cached hosts not found:.*InvalidHostThatDoesNotExist**",
repetitions=6,
timeout=60,
look_behind_lines=500,
)
assert node4.wait_for_log_line(
"Cached hosts dropped:.*InvalidHostThatDoesNotExist.*"
)