Hi dear developpers team and community, this if following case 07426946 where I was asked to post my question here.
I deployed a new ATS + ADH + ADS setup today in 
production, and I am continuously seeing this error message into the 
RRCPDL-Source logs : 
-----
Fri Mar 08  10:58:34.871198 2019 /tmp/.rrcp/source.0.rrmp: WARNING: 
[../Wrapper/Userlevel/rrcpCW_NetMgr.c,NetMgr_sendPkt(),274]
  error writing to the network:
------
Then ADS logs packet losses : 
-------
 RRCP STATUS MSG: RRCP_BC_MISSEDMSGS: gap in broadcast msgs from node 
169752968 (10.30.57.136) From Port 37000
--------
The RRCPDL parameters are : 
------
[pars3pmdsc527:/rmds/users/mdadmin] rrdump source -DL -port 37000 -P
rrdump v6.7.F30: [423]:Connected with RRCP-daemonless, Version 
rrcp6.7.T25(6070025), Control Port: 37000
RRCP Parameter Values (IpAddr: 10.30.57.136 (169752968) source mode, 
device /tmp/.rrcp/source.1):
RRCP process version (6070025)
Ip Addr          =  10.30.57.136 (169752968)
network          =  10.30.57.136
recvAddr         =  0.0.0.0 (INADDR_ANY)
MCRecvPort       =  37002 (0x908a)
MCSendToPort     =  37001 (0x9089)
PPPort           =  37000 (0x9088)
MCSendFromPort   =  (0) not configured
devicePath       =  /tmp/.rrcp/source.0.rrmp
packetSize       =  3100
maxPktPoolSize   =  200000
pktPoolLimitHigh =  190000
pktPoolLimitLow  =  180000
shuffleTolerance =  1024
userQLimit       =  65535
tdata            =  4
ndata            =  7
nrreq            =  3
trreq            =  4
twait            =  2
nmissing         =  128
tbchold          =  30
tpphold          =  29
nackDelayTime    =  20
bitmapFilter     =  0
logger.level     =  3
logger.file      =  /rmds/log/rrcpd/adh_0_source_rrcpdl.log
logger.maxSize   =  52428800
logger.maxSwapfiles     =  5
useIpMulticast          =  True
ipMultTTL               =  16
network                 =  net-feed
interface               =  10.30.57.136
sendMultAddress         =  239.254.0.168
recvMultAddress         =  239.254.0.169
hsmInterface            =  10.30.57.136
hsmMultAddress          =  239.254.0.117
hsmPort                 =  30101
hsmInterval             =  1
overflowMsgDump-oldest  =  1
maxUsers                     =  10
recvPortLow                  =  0
recvPortHigh                 =  0
udpSendBufSize               =  524288
udpRecvBufSize               =  524288
nackDelayTime                =  20
ackPackingRatio              =  10
weightPPRetransSent          =  1
weightPPRetransRcvd          =  1
weightBCRRequestSent         =  1
weightBCRRequestRcvd         =  1
congestionHiWaterMark        =  50
congestionLowWaterMark       =  15
congestionEvaluationInterval =  5
sessionProps                 =  (0x00000001)
   congestionControl         =  enabled
   switchReorderFix          =  disabled
   multiThreadEngine         =  disabled
clock tick                   =  100
--------
And some statistics : 
-------
RRCP Statistics (IpAddr: 10.30.57.136 (169752968) source mode, device 
/tmp/.rrcp/source.1):
--- Fri Mar  8 11:12:26 2019
Total pkts sent:             14937491      Rxmt'd PP pkts sent:         
    2191
BC pkts sent:                14931213      Unack'd PP pkts:             
     283
PP pkts sent:                    6278      RXMTREQPP pkts rcvd:         
     185
Total pkts rcvd:               920570      RXMTREQPP pkts sent:         
      25
BC pkts rcvd:                  912267      Msgs from users:             
14496073
PP pkts rcvd:                    8303      BC msgs from users:          
14493088
BC DATA pkts sent:           14493088      PP msgs from users:          
    2985
PP DATA pkts sent:               2985      Msgs to users:               
  433024
BC DATA pkts rcvd:             430193      DATA msgs to users:          
  432534
PP DATA pkts rcvd:               2341      BC DATA msgs to users:       
  430193
ACK pkts sent:                   1077      PP DATA msgs to users:       
    2341
ACKs sent:                       2341      STATUS msgs to users:        
     490
ACK pkts rcvd:                    843      Bad pkts/from user:          
       0
ACKs rcvd:                       2672      Bad pkts/from net:           
       0
PP DATA pkts ackd by wndw:         30      Discards/bad opcode:         
       0
RXMTREQs  staged:                   0      Discards/old BC:             
       0
RXMTREQs  canceled:                 0      Discards/old PP:             
       0
RXMTREQ pkts sent:                  0      Discards/rxmt'd PP:          
       0
RXMTREQs  sent:                     0      Msgs filtered out:           
       0
Rxmt'd RXMTREQ pkts sent:           0      Loop Msg filtered out:       
       0
Rxmt'd RXMTREQs  sent:              0      BC msgs misordered:          
       0
Rxmt'd BC pkts rcvd:                0      PP msgs misordered:          
       0
DISCARD pkts rcvd:                  0      Lost data/BC gaps msgs:      
       0
RXMTREQ pkts rcvd:               1279      Lost data/BC packets:        
       0
RXMTREQs rcvd:                   1819      Lost data/PP gaps msgs:      
      25
Rxmt'd RXMTREQ pkts rcvd:        3655      Lost data/PP packets:        
      26
Rxmt'd RXMTREQs rcvd:            5457      Lost data/node resync:       
       0
Rxmt'd BC pkts sent:             2137      Lost data/msg dscrd'd:       
       0
DISCARD pkts sent:                  0      Lost data/incmplt msg:       
       0
NULL pkts sent:                435988      Lost data/user Q overflow:   
       0
NULL pkts rcvd:                482074      Pkt buffers in use:          
       6
Heartbeats sent:                    0      Msg buffers in use:          
       5
Heartbeats rcvd:                    0      Total bytes sent:          
2156837849
Rxmt'd PP pkts rcvd:                0      Total bytes recv:            
45516739
-----
We checked the server (cables, CRC errors, soft errors), and cannot see 
any, can you please help to understand why this is failing ? 
Even if there is a very small trafic onto this server pair, it looks 
like RRCPd lost a lot of packets and this, regularly. I am not sure if 
there is a coincidence with the fact that the ATS "listens" to the ADH 
hotstandby state and maybe it creates trafic, I really don't know.
Any help will be appreciated !
Thanks,
Julien
(ps : I am afraid that the formatting of the statistics will not be helpful here , but it displays well in the support ticket).