spencer@hel-fire.arpa (SSD|tyrol) (05/25/88)
Hello,
I must apologize for such a lengthy message, but I have a problem that
has me really confused. I am the novice network administrator for one of
the HEL's LAN (see LAN below), and have been experiencing a problems with
transmissions to the MILNET.
LAN
---
I maintain a subnet attached to the main BRLNet via a AGS Cisco gateway.
Attached to this subnet are several types of systems including INTEL 320's,
VAX (VMS), MAC's, PC's, and an ISI. The gateway is use to convert TCP/IP
and 1822 protocols. The Intel operate with XENIX 3.4 operating system, the
VAX VMS, and the ISI uses 4.2 BSD UNIX. Additionally, the INTEL's use
CMC's TCP/IP board; the VAX uses Wollongong's TCP/IP board and the ISI has
EXCELAN's board.
The Problem
-----------
Each system on the subnet (i.e. INTEL's and VAX machines) communicate
properly with other systems on the MILNET with the exception of the ISI
machine. This machine (CCLHD.ARPA IP #192.12.67.20) has difficulty
communicating with other system on the MILNET when packet size exceed 509
bytes (the 509 bytes are data size--does not include headers etc.). When a
file, exceeding the 509 bytes, is attempted to be transferred (PUT) on
another system, FTP locks up. However, the ISI system can 'GET' a file of
any size (within reason).
The same occurs with E-mail. I thought that the problem was the Cisco
gateway was fragmented packages improperly, however, I have an tmp account
on STL-HOST1 (a TOP20 system), and I ftp'd a 1500 byte file without an
error. I don't feel reassemble of the packages are a problem because I am
testing this with a couple of BRL machines, and have the problem with both.
Questions
---------
Has anyone experienced this? Do you have a solution?
Can you provide suggestions?
Thanks,
Ron Spencer
spencer@hel-fire.arpa