steve@alberta.UUCP (Steve Sutphen) (08/19/87)
As we have progressed to more than a few Sun diskless workstations (30+)
sharing the same Ethernet cable and are now thinking of adding more I
am trying to figure out how to best configure the network. Two
possible solutions to the "too many packets on one network" come to
mind and I cannot really decide between them. The basic configuration
is like:
backbone Ethernet
---------T---------------------T-----------T---------T-----------------
| | | |
| | | ... |
----------------- |
| NFS/ND server | ------ some clients
|w/ large disk | | ? |-----T
----------------- ------ |
+---
| .
| . Some more clients
| .
|
+---
|__________
second Ethernet
Where "?" is the new machine and "second Ethernet" has yet to be
formed.
The problem is basically: should item "?" be a commercial bridge or
should it be a second Ethernet card on the file server for "Some more
clients" (if it is a bridge the ND file server will of course be put on
the "second Ethernet"). It should be obvious that the "file servers"
are Sun workstations in some form or another. The "file Server" for
the "second Ethernet" will not have much more disk space than is required to
put on the basic system (/usr, /, and /pub) -- not enough room for most
of the client user's private files (i.e. the clients will have to use
the gateway/bridge service to get their private NFS files from the
"large disk server").
The reason that this is a hard tradeoff to make is that a bridge is
about $5000 and the extra Ethernet card for the file server is $1400.
But, the server could be built with a 3/60 instead of a 3/140 if the space
wern't needed for the Ethernet Card. Also, in this case I would likely use
CDC Wren-IV SCSI drives instead of Fujitsu Eagles (with SMD interfaces) and
save $6000.
What I am really looking at is the performance. Has anyone had any
experience with these two types of configurations?
steve.ron@topaz.rutgers.edu (Ron Natalie) (08/20/87)
Generally when you have two ethernets with diskless clients on both it is advantageous to put two ethernets on the server (one on each net).
schoff@nic.nyser.net (Martin Lee Schoffstall) (08/21/87)
Be advised that the performance of the 2nd ethernet controller in the VMEbus is noticeably worse. We've even been told that "...its not supported..." for diskless clients. Marty Schoffstall schoff@nic.nyser.net