JavaClient 2.x connection`s warning

i am using client 2.1.4, i run my client on Windows then it is slowly to connect with Couchbase and i received a warn that “DNS Reverse Lookup of is slow, took 9003ms”.But when i run it on CentOS,it is quickly connecting and no warning. What`s the reason?

We identified windows reverse dns lookup being awfully slow as one common source of connection timeout. We put that warning message in place specifically so that kind of slowness can be identified.

This is due to the OS and will only occur the first time the IP is resolved during the application lifecycle.
Two possible workarounds to test:

  • add a DNS entry for the IP and provide the hostname instead of the API to the SDK
  • add the IP to the host file of the OS

See for example user working around this issue in this forum post

thanks a lot ,i am adding the nodes IP to the hosts file,its working!