Duplication between 2 DR4100 failed with Replication failed 'Broken pipe' as seen below.
Error 2015/03/22 23:14:02 88 Data Plugin NetVaultDC Replication failed 'Broken pipe'
Error 2015/03/22 23:14:02 88 Data Plugin NetVaultDC Failed stopping optimised replication 'Broken pipe'
RDA Library error code: 26
Network configuration problem
Teaming mode not set correctly. 1 DR4100 was set as ALB, other one was LACP.
It is recommended that both DR’s use LACP
If a SonicWALL Firewall is configured as MPLS connection. One side may deep packet inspection enabled. Disabled this as this also causes backup failures.