How to run Couchbase servers in an aisle network of Sync Gateway?

Mobile Sync Gateway
,
1

I have deployed a testing Couchbase cluster in a isolated network (172.15.1.0/24)
These Couchbase servers also has a secondary network to connect with Sync Gateway (172.25.1.0/24)

I have deployed a Sync Gateway in that network (172.25.1.0/24)

config:

{
  "log": ["*"],
  "databases": {
    "db1": {
      "server": "http://172.25.1.2:8091",
      "bucket": "default",
      "users": { "GUEST": { "disabled": false, "admin_channels": ["*"] } }
    }
  }
}

And I have the following errors:

2017-01-19T14:46:03.664Z Enabling logging: [*]
2017-01-19T14:46:03.667Z ==== Couchbase Sync Gateway/1.3.1(16;f18e833) ====
2017-01-19T14:46:03.667Z requestedSoftFDLimit < currentSoftFdLimit (5000 < 524288) no action needed
2017-01-19T14:46:03.667Z Opening db /db1 as bucket "default", pool "default", server <http://172.25.1.2:8091>
2017-01-19T14:46:03.667Z Opening Couchbase database default on <http://172.25.1.2:8091>
_time=2017-01-19T14:46:03.697+00:00 _level=INFO _msg= Trying with selected node 1 
_time=2017-01-19T14:46:03.697+00:00 _level=INFO _msg= Trying with http://172.15.1.2:8091/pools/default/bucketsStreaming/default 
2017-01-19T14:46:33.698Z WARNING: Bucket Updater for bucket default returned error: Get http://172.15.1.2:8091/pools/default/bucketsStreaming/default: dial tcp 172.15.1.2:8091: i/o timeout -- base.GetCouchbaseBucket.func1() at bucket.go:405
2017-01-19T14:46:33.698Z WARNING: Lost TAP feed for bucket default, with error: Get http://172.15.1.2:8091/pools/default/bucketsStreaming/default: dial tcp 172.15.1.2:8091: i/o timeout -- rest.(*ServerContext)._getOrAddDatabaseFromConfig.func1() at server_context.go:352
_time=2017-01-19T14:46:33.698+00:00 _level=ERROR _msg= Bucket Updater exited with err Get http://172.15.1.2:8091/pools/default/bucketsStreaming/default: dial tcp 172.15.1.2:8091: i/o timeout 
2017-01-19T14:48:10.950Z WARNING: Error installing Couchbase design doc: Put http://172.15.1.2:8092/default/_design/sync_gateway: dial tcp 172.15.1.2:8092: getsockopt: connection timed out -- db.installViews.func1() at database.go:577
2017-01-19T14:48:10.950Z Debug: RetryLoop retrying Attempt to install Couchbase design doc bucket : sync_gateway after 5 ms.
_time=2017-01-19T14:48:10.955+00:00 _level=INFO _msg= Trying with selected node 1 
2017-01-19T14:50:18.182Z WARNING: Error installing Couchbase design doc: Put http://172.15.1.2:8092/default/_design/sync_gateway: dial tcp 172.15.1.2:8092: getsockopt: connection timed out -- db.installViews.func1() at database.go:577
.............
.............

Correct openning the db1 in 172.25.1.2, but trying to connect to the internal Couchbase server network 172.15.1.2 that is not configured.

What is the way to deploy the Sync Gateway not in the Couchbase Server network?

Or it is necessary that sync remains in the Couchbase Servers “main” network.

Thanks in advance.