items are not replicated in bidirectional xdcr

./testrunner -i /tmp/ubuntu-64-2.0-biXDCR-tmp.ini -t xdcr.biXDCR.bidirectional.load_with_async_ops_and_joint_sets,ctopology=chain,rdirection=bidirection,sasl_buckets=1,doc-ops=create,doc-ops-dest=create,replication_type=xmem,get-cbcollect-info=True,eviction_policy=fullEviction,dgm_run=true,active_resident_threshold=90,items=2500,value_size=1024

steps to reproduce:
1)2 clusters with 2 buckets each, fullEviction policy, resident ratio 90 or less, load items
2)setup xdcr bidirectional

expected:
items are replicated

actual:
items are not replicated. Log is full of
Checkpointing related POST to http://Administrator:password@172.23.106.207:8092/_pre_replicate failed: {econnrefused,
[{lhttpc_client,
send_request,
1,
[

{file, "/home/buildbot/ubuntu-1004-x64-300-builder/build/build/couchdb/src/lhttpc/lhttpc_client.erl"},
{line, 199}]},
{lhttpc_client,
execute,
9,
[{file, "/home/buildbot/ubuntu-1004-x64-300-builder/build/build/couchdb/src/lhttpc/lhttpc_client.erl"}

,

{line, 151}

]},
{lhttpc_client,
request,
9,
[

{file, "/home/buildbot/ubuntu-1004-x64-300-builder/build/build/couchdb/src/lhttpc/lhttpc_client.erl"}

,

{line, 83}

]}]}
will attach cbcollects