Hi All
Sorry for late summary, but just back from evaluating backup solutions.
Long wave GBICS and single mode (dark fibre) will work. These GBICS are more
expensive than single mode. They are certified up to 10 km but can go to 100
km in some configurations.
Here are the replies, thanks to all.
--- Leonard, Nick ---
Long wave GBICS and single mode (dark fibre) expensive but will work
--- Davis, Alan ---
9-micron long wave single-mode optical fibre cables may be used for
inter-switch links up to 10km. This is conservative, going by a doc on the
website. I seem to remember seeing numbers like 70km total fabric length for
the latest releases, but that assumes that you are cascading switches no
more than 10km apart. It's also possible to use a FC/ATM bridge to extend
the link at the cost of adding latency.
--- Robert Sandford ---
Compaq have GBIC modules that will support distances up to 100 kilometers
(about 60 miles). Compaq SANworks call this "Very Long Distance GBIC"
which operates at 1062.5 megabits per second over 9-micron, single-mode
fiber.
--- Greg Freemyer ---
The long waves can definitely go that far. (10 Km currently supported, and I
think up to 100 Km in some circumstances.)
The long wave requires 9 micron fibre, and it REQUIRES a switch at each end.
(i.e. very expensive)
I believe there is one exception to the switch at each end rule. (and you
qualify.)
If you have a remote backup system, you can use a hub at each end. (Hubs are
a lot cheaper than switches.)
I don't know if they officially support a "switch - long wave - hub" solution
or not. I would expect it to work, but support is important to most people.
The main thing to realize is Compaq does NOT support long-wave directly into
a server or a storage/tape system.
--- Vlack, Jay from Compaq ---
You are correct. Multi-mode Fibre Channel optical cables should be used
with shortwave GBIC modules, and the cable should be 500m or less in
length. Single-mode Fibre Channel optical cables are used with longwave
GBIC modules, and the cable length can be up to 10km.
---
That's all folks
-----Original Message-----
From: Hannes Visagie
Sent: Friday, November 02, 2001 10:20 AM
To: tru64-unix-managers_at_ornl.gov
Subject: Max length of fibre
Hi All
We are investigating a new backup solution. I need to determine if we can
move out tape library offsite.
16 Port fibre switch to MDR {Fibre to SCSI} to Tape library.
AFAIK the short-wave GIBIC's can only do 500m.
long wave or other solution ?
We need about 5 Km. No problem with our Extreme TCP/IP net.
Thanks
Hannes
Received on Thu Nov 08 2001 - 05:33:49 NZDT