Loopback host address ('localhost','127.0.0.1', etc.) resolves to network IP

Expected behavior

I have my Jedis client configured to connect to localhost. I expect the connection to be made to the localhost via loopback.

Actual behavior

As of the changes in https://github.com/xetorthio/jedis/pull/1342, when specifying a localhost address, it now resolves to my machine’s network ip address.

This makes it impossible to connect to a redis-sentinel on localhost because the sentinel only allows connections from loopback on more recent versions of Redis.

Steps to reproduce:

1. Initialize a Jedis 2.9.+ client with the host 'localhost'
2. Unable to connect to local redis-sentinel (version 3.2.2) because 'localhost' resolved to an external ip (i.e. 10.1.10.254).

I think the new behavior in getLocalHostQuietly() introduces system-dependent behavior via InetAddress.getLocalHost().getHostAddress(), which does not seem to be the intent of the code.

Redis / Jedis Configuration

Jedis version:

2.9.x (since https://github.com/xetorthio/jedis/pull/1342)

Redis version:

3.2.2

Java version:

java version "1.8.0_40"
Java(TM) SE Runtime Environment (build 1.8.0_40-b26)
Java HotSpot(TM) 64-Bit Server VM (build 25.40-b25, mixed mode)

[yuriyz]

One of possible workarounds is to set it explicitly

HostAndPort.setLocalhost("127.0.0.1");

then jedis will not try to resolve it.

[sazzad16]

From Jedis 3.6.0 (due to #2445), there are two new constructors with Set<HostAndPort> sentinels param. These constructors will not convert the hosts and treat the hosts as they are provided.