Couchbase Unknown host in bootstrap list

I have a cluster of 2 machine and when I start my service that makes the connection log to me as the following error:

[PORTAL] 776296 [http-bio-9090-exec-63] INFO  com.couchbase.client.core.CouchbaseCore  - CouchbaseEnvironment: {sslEnabled=false, sslKeystoreFile='null', sslKeystorePassword='null', queryEnabled=false, queryPort=8093, bootstrapHttpEnabled=true, bootstrapCarrierEnabled=true, bootstrapHttpDirectPort=8091, bootstrapHttpSslPort=18091, bootstrapCarrierDirectPort=11210, bootstrapCarrierSslPort=11207, ioPoolSize=3, computationPoolSize=3, responseBufferSize=16384, requestBufferSize=16384, kvServiceEndpoints=1, viewServiceEndpoints=1, queryServiceEndpoints=1, searchServiceEndpoints=1, ioPool=NioEventLoopGroup, coreScheduler=CoreScheduler, eventBus=DefaultEventBus, packageNameAndVersion=couchbase-java-client/2.2.7 (git: 2.2.7, core: 1.2.8), dcpEnabled=false, retryStrategy=BestEffort, maxRequestLifetime=180000, retryDelay=ExponentialDelay{growBy 1.0 MICROSECONDS, powers of 2; lower=100, upper=100000}, reconnectDelay=ExponentialDelay{growBy 1.0 MILLISECONDS, powers of 2; lower=32, upper=4096}, observeIntervalDelay=ExponentialDelay{growBy 1.0 MICROSECONDS, powers of 2; lower=10, upper=100000}, keepAliveInterval=30000, autoreleaseAfter=2000, bufferPoolingEnabled=true, tcpNodelayEnabled=true, mutationTokensEnabled=false, socketConnectTimeout=1000, dcpConnectionBufferSize=20971520, dcpConnectionBufferAckThreshold=0.2, dcpConnectionName=dcp/core-io, callbacksOnIoPool=false, queryTimeout=180000, viewTimeout=75000, kvTimeout=2500, connectTimeout=5000, disconnectTimeout=25000, dnsSrvEnabled=false}
[PORTAL] 776367 [http-bio-9090-exec-63] INFO  com.couchbase.client.core.message.cluster.SeedNodesRequest  - Unknown host in bootstrap list.
	at Method)
	at com.couchbase.client.core.message.cluster.SeedNodesRequest.<init>(

after this error log write :

[PORTAL] 776625 [cb-io-1-1] INFO  com.couchbase.client.core.node.Node  - Connected to Node
[PORTAL] 776948 [cb-computations-3] INFO  com.couchbase.client.core.config.ConfigurationProvider  - Opened bucket test_bucket
[PORTAL] 776984 [cb-io-1-2] INFO  com.couchbase.client.core.node.Node  -

Hi @Alessandro.79,

Are you writing Java and using the Couchbase Java SDK? It looks like you’re trying to connect to, and that host is unable to be found. Are you sure that’s a correct host name?

i write in java and using a java sdk (java-client-2.2.7.jar)
i using a cluster of 2 server node with url :
and i use:

protected static final CouchbaseEnvironment ENV = DefaultCouchbaseEnvironment
cluster = CouchbaseCluster.create(ENV, url);

when url is couchbase01.xx,

1 Like

@Alessandro.79 the log is unambiguous. Your application is trying to lookup the ip address of and the address resolver is not able to find it.

If you’re able to connect in other ways to, you’ll need to look at how resolves hostnames on your system. This has nothing to do with Couchbase directly, so if you need to diagnose the problem you might want to write a simple Java app that just calls directly.