I would like to install some Gb switches and NIC's. Will they work with my
existing cat5 cable or do I need cat5e to do this?
Steve,
Per Cisco you can use Cat5, but remember, like the minimum requirements of
2000 server, just because it'll work doesn't mean you'll get the performance
you might expect.
Make sure that your patch panels and jacks are at least cat 5, implement GB
over Cu and upgrade things in a rolling fashion with the end goal of Cat 6
everywhere.
Also, remember that most GB switches aggregate ports in the backplane. This
means you'll get a bottleneck if you locate high utilization GB servers
close together on the same switch or blade. (4506 blades have this problem,
as does all Foundry equipment)
http://www.cisco.com/en/US/products/hw/switches/ps646/products_white_paper09186a008009268a.shtml
Ryan Hanisco
MCSE, MCDBA
Flagship Integration Services
im about to put in a cicso gigabit switch, but only gigabit for the
server - the rest of the network devices will be running at 100
what real world performace should i see over my existing 10/100 3com
switch seeing as the 20 pc's will be pulling data from the 1000 port
rather than a 100 port assuming the current switch is fully utilised?
If the server is the only gig device, then why would you expect to see
any difference?
The only performance difference would be the back-plane in the switch,
not in the port speed (since the workstations are only 100 base.
jas0n said:because currently I have 20 pc's all hitting the server and copying
large files/lots of small files back and forth, etc, so 20 pc's are all
sharing the servers 100 base connection to the switch - if we replace
the switch and the server gets a 1000 connection then my thinking was
the server can send/receive more data more quickly so they will see an
increase in speed to their max 100 base speed. is my logic here flawed?
because currently I have 20 pc's all hitting the server and copying
large files/lots of small files back and forth, etc, so 20 pc's are all
sharing the servers 100 base connection to the switch - if we replace
the switch and the server gets a 1000 connection then my thinking was
the server can send/receive more data more quickly so they will see an
increase in speed to their max 100 base speed. is my logic here flawed?
You will see an increase in performance.
The idea that there will be a speed limit to the lowest common denominator
is wrong.
Scott said:Yes, you should try multiple nics instead.
Scott
"Phillip Windell" said:If the Switch has a gig Port and the Server connects to it with a GIG that
is fine. the fact that the PCs run on 100 is also fine,...and desirable in
my opinion. The bottleneck would normally occur between the Server and the
Switch because that is the cable where the traffic from all PCs "merge".
If three PCs simultaneously pass a file with the Server at 100 then that
places a 300 load on the line between the Server and the Switch which the
Gig link would handle. Limiting the PCs with the 100 link is a good
thing,...if they also ran at 1000 then just one PC could "hog" the entire
"path" and you would be right back where you started from.
It is just like the road system you drive on,...you don't run an Interstate
Freeway right up to the end of your home's drive way. You have city streets
which dump onto larger city streets with heavier combined traffic, which
dump onto highways with more combined traffic, which dump onto Interstate
Freeways with even more combined traffic. As more and more traffic combines
together you use a larger road.
is fine. the fact that the PCs run on 100 is also fine,...and desirable in
my opinion. The bottleneck would normally occur between the Server and the
Switch because that is the cable where the traffic from all PCs "merge".
If three PCs simultaneously pass a file with the Server at 100 then that
places a 300 load on the line between the Server and the Switch which the
Gig link would handle. Limiting the PCs with the 100 link is a good
thing,...if they also ran at 1000 then just one PC could "hog" the entire
"path" and you would be right back where you started from.
It is just like the road system you drive on,...you don't run an Interstate
Freeway right up to the end of your home's drive way. You have city streets
which dump onto larger city streets with heavier combined traffic, which
dump onto highways with more combined traffic, which dump onto Interstate
Freeways with even more combined traffic. As more and more traffic combines
together you use a larger road.
I disagree. If the bottleneck is the server connection to the network,Leythos said:Seriously flawed. What you need is something called port trunking -
meaning that you install a card with more than one network port, they
come with 2 or 4 ports in many cases (or you can use multiple network
cards from the same vendor as long as they support the feature).
With trunking you get X amount of simultaneous communications paths -
one per port. This means the server can talk to X devices at the same
time.
If you want to make your life faster, just get some cheap $25 gig NIC's
and install them in the workstations that use the most network
bandwidth.
Think about your switch like this - each port gets a slice of the time
to talk with the server, but since the ports all talk at 100 speed
(except the server), nothing gets to the server port any faster, so it
doesn't really gain you anything. When you switch to all gig, or the
ones that use the network the hardest to gig, you will see an increase
in performance - and may also see an increase in CPU load on the server.