Hello,

  I am using DeleGate 8.7.8 on Linux gateway and have problems
  accessing an intranet FTP server from internet thru FTP proxy.
  I can connect to FTP server, CWD command works fine; but when I try
  to LS or RETR, it disconnects.
  The same happens if I try to connect thru proxy to FTP server on
  gateway itself (on localhost).
  Direct connection to FTP server on gateway from internet works fine.
  Gateway has ports 21 and 8021 (both TCP and UDP) open from internet.

  Here are the files:

  ------------ ftp.conf ------------
  -P8021
  SERVER=ftp
  RELIABLE=localhost,192.168.0.0/24,12.34.56.78
  RESOLV=dns,nis,file
  OWNER=nobody
  ADMIN=donskih@domain..ru
  EXPIRE=7d
  SRCIF="192.168.0.254:*:*:192.168.0.[0-254]:*"
  SRCIF="11.22.33.44:*:*:!192.168.0.[0-254]:*"
  PERMIT="*:*:192.168.0.[0-254]"
  PERMIT="*:*:12.34.56.78"
  PERMIT="*:*:localhost"
  ------------ end of ftp.conf ------------

  ------------ 8021 logfile ------------
  06/03 16:15:49.83 [28080] 3+0: -- Fork(OnetimeServer): 27975 -> 28080
  06/03 16:15:49.83 [28080] 3+0: (0) accepted [32] -@[12.34.56.78]external-client:4177 (0.004s)(1)
  06/03 16:15:49.83 [28080] 3+0: PATH: ftp://-:21!11.22.33.44:8021!external-client:4177!anonymous@external-client;1086264949
  06/03 16:15:49.85 [28080] 3+0: FTP server ftp://-:21/
  06/03 16:15:49.85 [28080] 3+0: bind_insock(21,11.22.33.44,0) = 0, errno=0
  06/03 16:15:50.86 [28080] 3+0: ## connect[21] TIMEOUT(1000)
  06/03 16:15:50.86 [28080] 3+0: ### IDENT CONNECT(external-client:113) TIMEOUT(1000ms) (110)
  06/03 16:15:50.86 [28080] 3+0: #### no authorization required
  06/03 16:15:50.86 [28080] 3+0: gethostbyname(-) unknown[0.00s]
  06/03 16:15:50.86 [28080] 3+0: default netmask 12.34.56.78/. = FFFFFF00
  06/03 16:15:50.86 [28080] 3+0: ## hostIFto 12.34.56.78 < 11.22.33.44 (ffffff00)
  06/03 16:15:50.86 [28080] 3+0: default netmask 12.34.56.78/. = FFFFFF00
  06/03 16:15:50.86 [28080] 3+0: FTP LOGIN FROM external-client TO donskih@domain..ru
  06/03 16:15:50.86 [28080] 3+0: PATH: ftp://internal-ftp.domain.ru:21!11.22.33.44:8021!external-client:4177!anonymous@external-client;1086264949
  06/03 16:15:50.88 [28080] 3+0: FTP server ftp://internal-ftp.domain.ru:21/
  06/03 16:15:50.88 [28080] 3+0: FTPHOPS: 1 [12/32 - -1/-1]
  06/03 16:15:50.88 [28080] 3+0: default netmask 12.34.56.78/. = FFFFFF00
  06/03 16:15:50.88 [28080] 3+0: ConnectToServer: DFLT=ftp://internal-ftp.domain.ru:21 REAL=://:0
  06/03 16:15:50.88 [28080] 3+0: [22] source port = 192.168.0.254:0 = 192.168.0.254:50257
  06/03 16:15:50.88 [28080] 3+0: ConnectToServer connected [22] {192.168.0.1:21 <- 192.168.0.254:50257} [0.001s]
  06/03 16:15:50.88 [28080] 3+0: default netmask 12.34.56.78/. = FFFFFF00
  06/03 16:15:50.91 [28080] 3+0: default netmask 12.34.56.78/. = FFFFFF00
  06/03 16:15:50.93 [28080] 3+0/1: default netmask 12.34.56.78/. = FFFFFF00
  06/03 16:15:50.93 [28080] 3+0/2: LoginPWD: "/"
  06/03 16:15:50.95 [28080] 3+0/2: default netmask 12.34.56.78/. = FFFFFF00
  06/03 16:15:50.97 [28080] 3+0/3: default netmask 12.34.56.78/. = FFFFFF00
  06/03 16:15:51.00 [28080] 3+0/4: default netmask 12.34.56.78/. = FFFFFF00
  06/03 16:15:54.59 [28080] 3+0/5: default netmask 12.34.56.78/. = FFFFFF00
  06/03 16:15:54.61 [28080] 3+0/6: default netmask 12.34.56.78/. = FFFFFF00
  06/03 16:15:54.61 [28080] 3+0/7: SRCIF=11.22.33.44:* [ftp-data-pasv://11.22.33.44:8021]
  06/03 16:15:54.61 [28080] 3+0/7: FTP-control-remote: 11.22.33.44:8021
  06/03 16:15:54.61 [28080] 3+0/7: SRCIF=11.22.33.44:* [tcpbound://12.34.56.78:4177]
  06/03 16:15:54.61 [28080] 3+0/7: FTP-data-local[23]: 11.22.33.44:50258
  06/03 16:15:54.61 [28080] 3+0/7: SRCIF=192.168.0.254:* [ftp-data-pasv-src://192.168.0.1:21]
  06/03 16:15:54.61 [28080] 3+0/7: ftp_conndata: connected 192.168.0.254:50256->internal-ftp.domain.ru/192.168.0.1:3413 [24]
  06/03 16:15:54.61 [28080] 3+0/7: -- with PASV
  06/03 16:15:54.61 [28080] 3+0/7: PASV [B][11,22,33,44,196,82] >> 227 Entering Passive Mode (11,22,33,44,196,82).^M
    (...and then it disconnects...)
  06/03 16:16:14.94 [28080] 3+0/7: disconnected [32] -@[12.34.56.78]external-client:4177 (25.111s)(0)
  ------------ end of 8021 logfile ------------

  Here, gateway has two interfaces, 192.168.0.254 and 11.22.33.44
  External client is 12.34.56.78, and intranet FTP server is 192.168.0.1

  Thanks in advance for any help.
  
--
Best regards,
 Dmitry                          mailto:piyfabdyi-mxhgu43wr33w.ml@delegate.org