Hi.
We have issue with pound.
Sometimes apache cannot get X-Forwarded-For. Most requests seem to be handles
definitely, but are not sometimes - about 3% - so.

Pound which run on Xen that have 4 back-end servers. Number of requests/sec
which handled with pound is about 10.　The suspicious thing does not
appear in log.

/etc/pound/pound.cfg is as follows.
LogLevel 3
LogFacility local1
DynScale 1

ListenHTTP
  Address x.x.x.x
  Port 80
  HeadRemove "X-Forwarded-For"
End


Service
  URL "^/sv3/.*"
  BackEnd
    Address 10.1.1.16
    Port 80
  End
End

Service
  URL "^/sv4/.*"
  BackEnd
    Address 10.1.1.17
    Port 80
  End
End


Service

  BackEnd
    Address 10.1.1.8
    Port 80
  End

  BackEnd
    Address 10.1.1.9
    Port 80
  End

  BackEnd
    Address 10.1.1.16
    Port 80
  End

  BackEnd
    Address 10.1.1.17
    Port 80
  End

  Session
    Type IP
    TTL 900
  End

End


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