Cydrome Leader wrote:
> Eric <einazaki668@yahoo.com> wrote:
>
>>On Apr 2, 8:39 am, Cydrome Leader <prese...@MUNGEpanix.com> wrote:
>>
>>>Eric <einazaki...@yahoo.com> wrote:
>>>
>>>>I have an Ultra 10 running Solaris 8 controlling a mass spectrometer
>>>>via an ethernet connection.
>>>>We can also connect to the Ultra via ssh to download files and do
>>>>whatever.
>>>
>>>>Lately it seems, when people are downloading files the connection to
>>>>the mass spec gets stomped
>>>>and the program that handles communication between the Ultra and the
>>>>mass spec dies or stalls.
>>>>I'm told it doesn't happen all the time, but fairly often.
>>>
>>>>The Ultra 10, the mass spec, a printer and a PC all connect to a hub
>>>>(an Inmac Microhub 4
>>>>4x10BaseT + AUI hub). Further, there's a connection between the hub
>>>
>>>ha, wow. an inmac. How old is this thing?
>>>
>>>I'd suggest replacing hubs or checking cables before tossing in new nics,
>>>especially considering that 10Mb networks aren't going to tax an ultra10
>>>in the first place.
>>
>>We've had the mass spec for about seven years. It was also the mfg's
>>proto
>>so the instrument itself is probably around ten or more years old. If
>>that hub
>>was with the instrument the whole time I wouldn't be a bit surprised.
>>
>>And tell me, when was the last time you saw an AUI connector on
>>anything?
>
>
> With a few days actually, on an Ascent ISDN terminal adapter, It was still
> "new" enough to have a RJ45 jack as well.
>
> In my box of legacy nonsense, I have an IBM branded AUI to 10base-2
> transciever.
>
> It's almost as silly as those older NICs that actually had 10base2,
> twister pair AND an AUI port.

I think I might have one those too. DE400-???

Eric <einazaki668@yahoo.com> wrote:
> Rick:

> What's a "plain" 10BT switch?

My poor wording for a switch that only speaks 10BT.

> Everything I've seen over the last several years have been 10/100
> switches. The switch I'm thinking of using is a 10/100BT switch
> with (they say) auto config of speed, xover, and duplex.

OK, so you could indeed see a 10X increase in potential bandwidth out
of a single system.

> Let me clarify, the downloading is going _from_ the Sun into the
> cloud, mostly.

OK. I guess there could be short bursts then of "capture effect" with
the Sun grabbing the ether and not letting go.

You mentioned ssh - are the downloads tunneling through that or
otherwise encrypted?

> Typically, the Sun is talking to the mass spec, let's say, all the
> time. Sometimes to frequently someone(s) from a remote pc will
> connect to the Sun to run an interactive shell session or transfer
> files. That's a day in the life of the mass spec's network.

> CPU utilization and maybe a snoop/tcpdump study (gotta figure out
> how to run snoop/tcpdump first, though).

tcpdump -i <interface> -w <tracefile>

will run tcpdump over the specified interface, storing the packets it
captures into <tracefile> for later analysis using tcpdump -r or some
other utility able to read tcpdumps dumpfiles.

rick jones
--
denial, anger, bargaining, depression, acceptance, rebirth...
where do you want to be today?
these opinions are mine, all mine; HP might not want them anyway...
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

On Apr 3, 3:01 pm, Rick Jones <rick.jon...@hp.com> wrote:

>
> You mentioned ssh - are the downloads tunneling through that or
> otherwise encrypted?
>

Well, all our remote access to the Sun is via either sftp or the
ssh client. So the downloads are encrypted but only to the
extent that sftp is encrypted. And we're not doing stuff like
running ftp or X sessions through an ssh tunnel if that's what
you mean by tunneling.

Seeing as how the mass spec's computer is only running 10Mb/s
(I think), I've got a pretty good feeling about this switch business.

thanks,
eric

Richard B. Gilbert <rgilbert88@comcast.net> wrote:
> Cydrome Leader wrote:
>> Eric <einazaki668@yahoo.com> wrote:
>>
>>>On Apr 2, 8:39 am, Cydrome Leader <prese...@MUNGEpanix.com> wrote:
>>>
>>>>Eric <einazaki...@yahoo.com> wrote:
>>>>
>>>>>I have an Ultra 10 running Solaris 8 controlling a mass spectrometer
>>>>>via an ethernet connection.
>>>>>We can also connect to the Ultra via ssh to download files and do
>>>>>whatever.
>>>>
>>>>>Lately it seems, when people are downloading files the connection to
>>>>>the mass spec gets stomped
>>>>>and the program that handles communication between the Ultra and the
>>>>>mass spec dies or stalls.
>>>>>I'm told it doesn't happen all the time, but fairly often.
>>>>
>>>>>The Ultra 10, the mass spec, a printer and a PC all connect to a hub
>>>>>(an Inmac Microhub 4
>>>>>4x10BaseT + AUI hub). Further, there's a connection between the hub
>>>>
>>>>ha, wow. an inmac. How old is this thing?
>>>>
>>>>I'd suggest replacing hubs or checking cables before tossing in new nics,
>>>>especially considering that 10Mb networks aren't going to tax an ultra10
>>>>in the first place.
>>>
>>>We've had the mass spec for about seven years. It was also the mfg's
>>>proto
>>>so the instrument itself is probably around ten or more years old. If
>>>that hub
>>>was with the instrument the whole time I wouldn't be a bit surprised.
>>>
>>>And tell me, when was the last time you saw an AUI connector on
>>>anything?
>>
>>
>> With a few days actually, on an Ascent ISDN terminal adapter, It was still
>> "new" enough to have a RJ45 jack as well.
>>
>> In my box of legacy nonsense, I have an IBM branded AUI to 10base-2
>> transciever.
>>
>> It's almost as silly as those older NICs that actually had 10base2,
>> twister pair AND an AUI port.
>
> I think I might have one those too. DE400-???

not sure of the model, but it had amber lights and is just big enough that
it needs to attach to the AUI port with some 1980s IBM-ish overly thick
cable. It's not nearly as large as the Synoptics ash tray sized
transcievers though.

Doug McIntyre <merlyn@geeks.org> wrote:
> Cydrome Leader <presence@MUNGEpanix.com> writes:
>>It's almost as silly as those older NICs that actually had 10base2,
>>twister pair AND an AUI port.
>
> Why is that silly?

They were such a hassle to use. You had to keep a stack of softset config
diskettes to see how each card was configured.

As I mentioned with SCSI cards somewhere else, there were many more
choices of cards years ago than these days.

The first 10/100 cards were retarded like that as well. I recall setting
speed on some 3com cards with a boot floppy because they didn't have
autonegotiation yet.

Dip switches on the rear of the card would have been most convenient for
stuff like that.

media converter always seem to have dip switches for the SQE stuff.

Eric <einazaki668@yahoo.com> wrote:
> Well, all our remote access to the Sun is via either sftp or the ssh
> client. So the downloads are encrypted but only to the extent that
> sftp is encrypted.

That thought was behind my asking about CPU utilization during these
downloads

I suppose the mass spectrometer isn't kind enough to have a way to
give you its link-level statistics If it were, to check on the
capture effect question, you would check them for "excessive retries"
(or something like that) which would be sufficient but not necessary
to show capture effect. Capture effect is when one host on the
CSMA/CD network is able to transmit fast enough to get back-to-back
frames on the wire, and cause other stations to have their backoff
timers keep growing. That could put some serious delays into the
communications. When one is able to run full-duplex (ie with a switch
rather than a hub) then there is no CSMA/CD any longer, so no capture
effect.

rick jones
--
denial, anger, bargaining, depression, acceptance, rebirth...
where do you want to be today?
these opinions are mine, all mine; HP might not want them anyway...
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

On Apr 3, 7:22 pm, Rick Jones <rick.jon...@hp.com> wrote:
> Eric <einazaki...@yahoo.com> wrote:
> > Well, all our remote access to the Sun is via either sftp or the ssh
> > client. So the downloads are encrypted but only to the extent that
> > sftp is encrypted.
>
> That thought was behind my asking about CPU utilization during these
> downloads
>
> I suppose the mass spectrometer isn't kind enough to have a way to
> give you its link-level statistics If it were, to check on the
> capture effect question, you would check them for "excessive retries"
> (or something like that) which would be sufficient but not necessary
> to show capture effect. Capture effect is when one host on the
> CSMA/CD network is able to transmit fast enough to get back-to-back
> frames on the wire, and cause other stations to have their backoff
> timers keep growing. That could put some serious delays into the
> communications. When one is able to run full-duplex (ie with a switch
> rather than a hub) then there is no CSMA/CD any longer, so no capture
> effect.
>
> rick jones
> --
> denial, anger, bargaining, depression, acceptance, rebirth...
> where do you want to be today?
> these opinions are mine, all mine; HP might not want them anyway...
> feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

You're thinking that ssh could be saturating the cpu and having a
trickle
down effect on the network interface?

As far as I know, this is a recent problem. The network
infrastructure
hasn't changed in some time (it's just as slow as it's ever been). I
don't see anything that would account for increased traffic, not
greatly increased, anyway. It may be that we got some new software
that's chewing up more cpu time.

I'm not expecting any help from the mass spec's SBC.

So if network capture is the problem, I wouldn't necessarily see it
from the Sun, the machine doing the capturing?

I'll probably find out sooner or later but, does snoop (on Solaris 8)
have a large cpu footprint? If it's set up to not do hostname lookup
does snoop introduce any network latency?

thanks,
eric

Eric <einazaki668@yahoo.com> wrote:
> You're thinking that ssh could be saturating the cpu and having a
> trickle down effect on the network interface?

Yep. Probability might be small.

> So if network capture is the problem, I wouldn't necessarily see it
> from the Sun, the machine doing the capturing?

Nope. That is the "fast" system able to grab and hold the ether while
the other stations' backoff timers grow. Actually I suppose it could
appear - you could see larger than normal gaps between requests sent
to the mass spectrometer and the replies back.

rick jones
--
web2.0 n, the dot.com reunion tour...
these opinions are mine, all mine; HP might not want them anyway...
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...