爲什麼我得到了NoHostAvailable：？

如果我運行這個簡單的查詢：爲什麼我得到了NoHostAvailable：？

SELECT * from myapp.latests WHERE organization_id = 1 and user_id = 1;

我得到錯誤：

NoHostAvailable:

運行nodetool status結果爲：

Datacenter: eu-central 
====================== 
Status=Up/Down 
|/ State=Normal/Leaving/Joining/Moving 
-- Address Load  Tokens  Owns (effective) Host ID        Rack 
UN 10.0.0.53 190.96 KiB 256   0.0%    80f8bf0a-c46d-41ce-bb2e-498def5b3792 1a 
UN 10.0.20.5 189.35 KiB 256   0.0%    f25fe4bf-29b2-4403-8e3e-4e973a5f26ab 1b 
UN 10.0.0.54 183.13 KiB 256   0.0%    c46ac05a-6cb2-48f1-a776-2c57c33e7719 1a

這裏是說明：

DESCRIBE myapp; 

CREATE KEYSPACE myapp WITH replication = {'class': 'NetworkTopologyStrategy', 'eu-central-1': '2'} AND durable_writes = true; 

CREATE TABLE myapp.locations (
    organization_id int, 
    user_id int, 
    date text, 
    unix_time bigint, 
    lat double, 
    long double, 
    PRIMARY KEY ((organization_id, user_id, date), unix_time) 
) WITH CLUSTERING ORDER BY (unix_time ASC) 
    AND bloom_filter_fp_chance = 0.01 
    AND caching = {'keys': 'ALL', 'rows_per_partition': 'NONE'} 
    AND comment = '' 
    AND compaction = {'class': 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy', 'max_threshold': '32', 'min_threshold': '4'} 
    AND compression = {'chunk_length_in_kb': '64', 'class': 'org.apache.cassandra.io.compress.LZ4Compressor'} 
    AND crc_check_chance = 1.0 
    AND dclocal_read_repair_chance = 0.1 
    AND default_time_to_live = 0 
    AND gc_grace_seconds = 864000 
    AND max_index_interval = 2048 
    AND memtable_flush_period_in_ms = 0 
    AND min_index_interval = 128 
    AND read_repair_chance = 0.0 
    AND speculative_retry = '99PERCENTILE'; 

CREATE TABLE myapp.latests (
    organization_id int, 
    user_id int, 
    lat double, 
    long double, 
    unix_time bigint, 
    PRIMARY KEY (organization_id, user_id) 
) WITH CLUSTERING ORDER BY (user_id ASC) 
    AND bloom_filter_fp_chance = 0.01 
    AND caching = {'keys': 'ALL', 'rows_per_partition': 'NONE'} 
    AND comment = '' 
    AND compaction = {'class': 'org.apache.cassandra.db.compaction.SizeTieredCompactionStrategy', 'max_threshold': '32', 'min_threshold': '4'} 
    AND compression = {'chunk_length_in_kb': '64', 'class': 'org.apache.cassandra.io.compress.LZ4Compressor'} 
    AND crc_check_chance = 1.0 
    AND dclocal_read_repair_chance = 0.1 
    AND default_time_to_live = 0 
    AND gc_grace_seconds = 864000 
    AND max_index_interval = 2048 
    AND memtable_flush_period_in_ms = 0 
    AND min_index_interval = 128 
    AND read_repair_chance = 0.0 
    AND speculative_retry = '99PERCENTILE';

有什麼想法？

來源

2017-03-06 simo

請檢查http://stackoverflow.com/questions/18724334/cant-connect-to-cassandra-nohostavailableexception 這個例外可能有很多原因。此錯誤消息主要表示客戶端無法連接到Cassandra主機。原因可能是因爲主機關閉或您的客戶端代碼出現問題或與主機的連接關閉。 – Kaushal

請檢查您的客戶端是否有權在9042端口上連接。如果您正在集羣上的cqlsh上運行它，請檢查端口在Cassandra節點（使用其他端口和協議（JMX））的節點之間是否打開。

來源

2017-03-06 16:11:04 nevsv

爲什麼我得到了NoHostAvailable：？

回答

相關問題