Help With Netwrok Speed

On 18/07/2005 Alex Fraser wrote:

> > I set up 'Jumbo Frames' on the Buffalo and the Intel NIC, they seem
> > a bit sensitive so that may have been an issue.
>
> What do you mean, "a bit sensitive"?

The TerraStation manual says they must match exactly but it uses 4100
and the NIC uses 4088, although a web search seems to indicate there
are different ways of measuring them :-(


> > The Buffalo does do RAID5 but my plan was to have a reasonably
> > fool-proof data back up that I could set up and forget, apart from
> > routine maintenance.
>
> How does RAID5 make a difference to this?

By running two back ups the data is effectively copied to four drives.
If one drive fails I can (a) use the data from the other array and (b)
replace the failed drive and have it re-build the array (in theory
without data loss). 250GB capacity is ample at the moment.


> > I wonder if I made a fundamental mistake in setting things up. I had
> > the Buffalo connected to the server using the Intel NIC and both
> > with fixed addresses in the 192.169.2.n range. The server was
> > connected to my home network using its second NIC, a Realtek, using
> > the router's DHCP and the 192.168.1.n range.
>
> I can't see any reason to think that is a "fundamental mistake". I
> would probably have done the same.
>
> [snip]
> > I have just re-configured things so I just use the Intel NIC and
> > both the server and Buffalo are connected directly to the router
> > using DHCP, although this means the Buffalo will now run at 100Mb/s.
>
> At the transfer rate you've given, that shouldn't make much (if any)
> difference.

Well it's just backed up the remaining 28,519 MB in 1hr 51 minutes,
that's greased lightning in comparison :-)

I'll see how the second back up goes, it started after the first one
finished.

It seems to me I can pin the speed problem down to either the gigabit
implementation (either on the Buffalo or the NIC) or the way I set it
up.

When I originally set things up I let both NIC's on the server use DHCP
which didn't work at all. What about using fixed IP addresses on the
TerraStation and the Gigabit NIC with a subnet mask of 255.255.0.0 on
all NIC's?


--
Jeff Gaines
Damerham Hampshire UK
Using XanaNews 1.17.5.7 http://www.wilsonc.demon.co.uk/d9xananews.htm

"Jeff Gaines" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> On 18/07/2005 Alex Fraser wrote:
[snip]
> > > The Buffalo does do RAID5 but my plan was to have a reasonably
> > > fool-proof data back up that I could set up and forget, apart from
> > > routine maintenance.
> >
> > How does RAID5 make a difference to this?
>
> By running two back ups the data is effectively copied to four drives.
> If one drive fails I can (a) use the data from the other array and (b)
> replace the failed drive and have it re-build the array (in theory
> without data loss). 250GB capacity is ample at the moment.

My question still stands . It's true that your setup can tolerate even
three drives failing, whereas RAID5 would only tolerate a single drive
failing, but there's a factor of three in capacity too.

> > > I have just re-configured things so I just use the Intel NIC and
> > > both the server and Buffalo are connected directly to the router
> > > using DHCP, although this means the Buffalo will now run at 100Mb/s.
> >
> > At the transfer rate you've given, that shouldn't make much (if any)
> > difference.
>
> Well it's just backed up the remaining 28,519 MB in 1hr 51 minutes,
> that's greased lightning in comparison :-)

Fairly respectable if the average file size is small, still a bit slow if it
is large.

[snip]
> It seems to me I can pin the speed problem down to either the gigabit
> implementation (either on the Buffalo or the NIC) or the way I set it
> up.

Sounds like it. Did you try the gigabit connection but without jumbo frames?

> When I originally set things up I let both NIC's on the server use DHCP
> which didn't work at all. What about using fixed IP addresses on the
> TerraStation and the Gigabit NIC with a subnet mask of 255.255.0.0 on
> all NIC's?

It's not clear what you mean, but I am quite sure the problem is nothing to
do with addressing.

Alex

On 18/07/2005 Alex Fraser wrote:

> > When I originally set things up I let both NIC's on the server use
> > DHCP which didn't work at all. What about using fixed IP addresses
> > on the TerraStation and the Gigabit NIC with a subnet mask of
> > 255.255.0.0 on all NIC's?
>
> It's not clear what you mean, but I am quite sure the problem is
> nothing to do with addressing.


Thanks for your reply Alex :-)

The second backup is still running, I have checked and found there are
44,952 scenery bitmap files in Flight Sim, pretty well all 47K and
that's where it really slows down. (I back up Flight Sim because it
takes so long to install with 12 scenery CD's on top of the 3 x app
CD's, it just runs anyway so doesn't need a re-install).

I would appreciate your input, if you have time, if I try to explain
the set up more clearly.

I have 2 x built in NIC's on the mobo, 1 is Intel Gigabit and the other
Realtek 100 Mb/s. I have a Draytek Vigor Modem/Router connected by a
long cable to a Linksys WAP in the spare room upstairs, this gives me
wireless coverage all over the bungalow.

The TerraStation can either work with a fixed IP address or use a DHCP
service, as of course can both he NIC's.

Originally I left everything on auto, i.e. get an IP address from the
Draytek. This meant that the server had 2 NIC's in the same address
range, say 192.168.1.10 and 1.11. I had real problems on the network,
not being able to see the server from the other PC's. I decide, rightly
or wrongly, that I needed different address ranges on each of the NIC's
so I set up the server Gigabit NIC as 192.168.2.1 (fixed) and the
TerraStation as 192.168.2.2 (also fixed). That was fine, I could see
the server from the other PC's but I couldn't see the TerraStation,
that's no problem as the primary source of data is a HD on the server.
In addition I could use the Gigabit connection at full speed since it
was just the server and TerraStation directly wired to each other with
no hub.

The Realtek NIC was plugged into the Linksys and worked at 100 Mb/s.

What went through my mind was that my speed problem might be the server
having to work out where each file needed to go (i.e. which NIC to
use)and being slowed down as a consequence - now I've read that it
looks daft but to some extent I've only got the home network running
because I plugged everything in and it worked, I am not a techie when
it comes to networks.

I'm now wondering whether copying nearly 45,00 files over any network
is just slow so perhaps I should go back to my original setup and gain
the advantage of Gigabit speed.

I would welcome your thoughts, particularly on whether the two NIC's in
the server can be in the same IP address range or not.

Hope that makes sense :-)

--
Jeff Gaines
Damerham Hampshire UK
Using XanaNews 1.17.5.7 http://www.wilsonc.demon.co.uk/d9xananews.htm

In message <(E-Mail Removed)>, Jeff Gaines
<(E-Mail Removed)> writes
>The second backup is still running, I have checked and found there are
>44,952 scenery bitmap files in Flight Sim, pretty well all 47K and
>that's where it really slows down. (I back up Flight Sim because it
>takes so long to install with 12 scenery CD's on top of the 3 x app
>CD's, it just runs anyway so doesn't need a re-install).
Could you zip the files to one large file before the backup? Doesn't
need to be anything but a container for the files, I.E. no compression,
so the backup utility doesn't have to handle that many small files.
>I'm now wondering whether copying nearly 45,00 files over any network
>is just slow so perhaps I should go back to my original setup and gain
>the advantage of Gigabit speed.
There doesn't appear to be *much* advantage to gigabit for this
particular device but if it's there you might as well use it and gain
the small speed up.
>
>I would welcome your thoughts, particularly on whether the two NIC's in
>the server can be in the same IP address range or not.
No problems, as long as they have different addresses they can share a
subnet.
>
>Hope that makes sense :-)
>

--
Clint Sharp

"Jeff Gaines" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
[snip]
> I would appreciate your input, if you have time, if I try to explain
> the set up more clearly.
>
> I have 2 x built in NIC's on the mobo, 1 is Intel Gigabit and the other
> Realtek 100 Mb/s. I have a Draytek Vigor Modem/Router connected by a
> long cable to a Linksys WAP in the spare room upstairs, this gives me
> wireless coverage all over the bungalow.
>
> The TerraStation can either work with a fixed IP address or use a DHCP
> service, as of course can both he NIC's.
>
> Originally I left everything on auto, i.e. get an IP address from the
> Draytek. This meant that the server had 2 NIC's in the same address
> range, say 192.168.1.10 and 1.11.

Really? Unless both NICs were attached to the router I don't see how.

> I had real problems on the network, not being able to see the server from
> the other PC's. I decide, rightly or wrongly, that I needed different
> address ranges on each of the NIC's so I set up the server Gigabit NIC as
> 192.168.2.1 (fixed) and the TerraStation as 192.168.2.2 (also fixed).

That's a perfectly normal configuration (assuming subnet masks of
255.255.255.0 all round).

> That was fine, I could see the server from the other PC's but I couldn't
> see the TerraStation, [...]

I assume you mean you couldn't see the TeraStation from the other PCs - that
would not be surprising since you would need to configure the relevant
routes on the PCs and the TS, and probably enable forwarding (routing) on
the server.

> What went through my mind was that my speed problem might be the server
> having to work out where each file needed to go (i.e. which NIC to
> use)and being slowed down as a consequence - now I've read that it
> looks daft but to some extent I've only got the home network running
> because I plugged everything in and it worked, I am not a techie when
> it comes to networks.

It shouldn't take any significant extra time.

> I'm now wondering whether copying nearly 45,00 files over any network
> is just slow so perhaps I should go back to my original setup and gain
> the advantage of Gigabit speed.

Except it appeared to be /slower/ that way...

> I would welcome your thoughts, particularly on whether the two NIC's in
> the server can be in the same IP address range or not.

Not usually; it's easiest to explain why with an example. Say you have:

Server NIC #1: 192.168.0.1/255.255.255.0, attached to switch.
Server NIC #2: 192.168.0.2/255.255.255.0, attached to TeraStation.
Another PC: 192.168.0.3/255.255.255.0, attached to switch.
TeraStation: 192.168.0.4/255.255.255.0, attached to Server NIC #2.

For each interface, the assumption (made by the OS) is that all addresses in
the same range as the address of the interface are reachable directly (ie
without going via a router/gateway) via that interface. But if you apply
this to both server NICs, there is a problem: to reach (say) the
TeraStation, which interface should the server choose?

OTOH, suppose you have two seperate address ranges, as you had above:

Server NIC #1: 192.168.1.10/255.255.255.0, attached to switch.
Server NIC #2: 192.168.2.1/255.255.255.0, attached to TeraStation.
Another PC: 192.168.1.11/255.255.255.0, attached to switch.
TeraStation: 192.168.2.2/255.255.255.0, attached to Server NIC #2.

Now the server has no problem choosing the interface.

There is (perhaps not too surprisingly) more to it than this, but what I
have attempted to illustrate is the basic problem. "Choosing the interface"
is a big part of routing - you can probably find out more on the web if you
are interested.

Alex

On 19/07/2005 Alex Fraser wrote:

[snipped]

Alex

Many thanks for your patience and all your help, it is much appreciated
and I have saved it in my help folder :-)

I have re-jigged it to use the Gigabit link as it seems daft not to use
the maximum speed. The backup at 100Mb/s was still running this morning
so even if these particular files are slow at Gigabit speed they're
even slower at 100Mb/s!

Thanks again.


--
Jeff Gaines
Damerham Hampshire UK
Using XanaNews 1.17.5.7 http://www.wilsonc.demon.co.uk/d9xananews.htm