[9fans] terminal + router + cable internet

[9fans] terminal + router + cable internet

[john]

I've got a PIII machine installed as a disk-bearing
terminal, but I want to have it grab root over the
Internet. It is behind a router, which is connected
to the cable modem. If I choose tcp at the "root from"
prompt, type in fs IP, auth IP, and username, I'll
eventually get prompted once again for username and
then password; the terminal then boots pretty normally
and works great. However, the time between when I type
fs and auth IPs and the time I type the username and
password is extremely long; I'd estimate something like
5 minutes or so. The same thing happened to me when
I was using a vmware terminal from Hawaii, but
I just chalked that up to the long distance and the
virtual machine.

Are any of you booting real terminals from behind
a router? At the moment, I don't have any ports
forwarded, and the terminal gets its IP through
DHCP. Should I set it up with a static IP and forward
some ports? Which ports would I need?

Thanks


John

Re: [9fans] terminal + router + cable internet

[Anthony Sorace]

getting your root fs over a wide-area network can be quite painful;
you're not moving a ton of data, but the process is very
latency-sensitive. i've not done it in a few years, but boot times of
5-10 minutes were not unusual. cfs(4) cut it to about a quarter that.

still, what i ended up doing was booting locally with a termrc that
connected to my file server and pulled in what i wanted. it was a bit
extra effort to maintain, but the time difference was more than
dramatic enough to make it worth it.

Re: [9fans] terminal + router + cable internet

[erik quanstrom]

> getting your root fs over a wide-area network can be quite painful;
> you're not moving a ton of data, but the process is very
> latency-sensitive. i've not done it in a few years, but boot times of
> 5-10 minutes were not unusual. cfs(4) cut it to about a quarter that.
>
> still, what i ended up doing was booting locally with a termrc that
> connected to my file server and pulled in what i wanted. it was a bit
> extra effort to maintain, but the time difference was more than
> dramatic enough to make it worth it.

what was the latency?  did you do any network debugging to see how
much traffic was moving between the terminal and fs?

the reason i ask is that at one point i had things miscofigured in
/lib/ndb/local and in the dns server that was serving my domain
so that even on a local gigabit network, startup took 10 minutes.
this wasn't due to network latency.

- erik

Re: [9fans] terminal + router + cable internet

[john]

> getting your root fs over a wide-area network can be quite painful;
> you're not moving a ton of data, but the process is very
> latency-sensitive. i've not done it in a few years, but boot times of
> 5-10 minutes were not unusual. cfs(4) cut it to about a quarter that.
>
> still, what i ended up doing was booting locally with a termrc that
> connected to my file server and pulled in what i wanted. it was a bit
> extra effort to maintain, but the time difference was more than
> dramatic enough to make it worth it.

The problem seems to be occurring *before* I authenticate myself, though,
which means the long delay isn't related to fetching from the fs, right?
I don't know much about the Plan 9 boot process, so I could be wrong.



John

Re: [9fans] terminal + router + cable internet

[Axel Belinfante]

> > getting your root fs over a wide-area network can be quite painful;
> > you're not moving a ton of data, but the process is very
> > latency-sensitive. i've not done it in a few years, but boot times of
> > 5-10 minutes were not unusual. cfs(4) cut it to about a quarter that.
> >
> > still, what i ended up doing was booting locally with a termrc that
> > connected to my file server and pulled in what i wanted. it was a bit
> > extra effort to maintain, but the time difference was more than
> > dramatic enough to make it worth it.
>
> The problem seems to be occurring *before* I authenticate myself, though,
> which means the long delay isn't related to fetching from the fs, right?
> I don't know much about the Plan 9 boot process, so I could be wrong.

for what it's worth:
in the past I occasionally booted a machine at home from an
fs at work, over cable modem + nat (wireless) router.
booting took usually quite a while.
this might be related to network throughput,
but maybe also with speed of machine.

now that I'm playing with parallels I also tried setting
up a floppy image to boot from the fs at work.
I boot recent 9pc.gz; the plan9.ini on the image sets auth and fs.
after selecting tcp boot methode the whole process
through the user/secstore passwd prompts till I get the term% prompt,
took about one and half minute (wall clock timing).
typing rio then and starting rio takes just a little while.
this on parallels v 3 on a recent (intel) imac.

timed again. 50 s from 'boot from tcp' till user: prompt,
immediately after that secstore prompt, then 50 s or so
till term% prompt.

cable modem connection is (I think) 1024/256.
regarding latency: ip/ping to the fs:
31: rtt 25969 mus, avg rtt 24092 mus ...


actually, when I use drawterm from machine at work to cpu
server at work the logging in might take quite a while.

Axel.

Re: [9fans] terminal + router + cable internet

[erik quanstrom]

> timed again. 50 s from 'boot from tcp' till user: prompt,
> immediately after that secstore prompt, then 50 s or so
> till term% prompt.
> 
> cable modem connection is (I think) 1024/256.
> regarding latency: ip/ping to the fs:
> 31: rtt 25969 mus, avg rtt 24092 mus ...
> 

(do you mean µs?)

i think this is a nameserver or network configuration
issue.  25ms is not too bad.  networks have gottten so
much faster we've had to move the decimal place to
the right three places.

- erik

Re: [9fans] terminal + router + cable internet

[Anthony Sorace]

i agree my experience isn't relevant to john's problem. his ping times
are about 1/5 or less of what mine were. more significantly, the fact
that his significant delay happens before authentication points
towards something in the auth process (factotum+secstore).

in general, though: networks have gotten faster, but not terribly much
quicker. there's been no significant change in latency between
machines i've been paying attention to in various parts of the US
(mostly east coast) and western europe (mostly London) for the past 4
years. the bandwidth (and bandwidth/$) have both improved
significantly.

(this is not true for asia, especially india, where i've seen very
significant improvements)

Re: [9fans] terminal + router + cable internet

[Francisco J Ballesteros]

We have booted a diskless octopus terminal (well, with our terminal
software in the terminal,
I admit)  while at greece, keeping the files at madrid. RTTs were
>150ms. A little bit
slower than at home (which is a little bit slower than a direct lan attach).

As far as our experience goes (which is not much), latency is the real problem.


On 9/13/07, Anthony Sorace <anothy@gmail.com> wrote:
> i agree my experience isn't relevant to john's problem. his ping times
> are about 1/5 or less of what mine were. more significantly, the fact
> that his significant delay happens before authentication points
> towards something in the auth process (factotum+secstore).
>
> in general, though: networks have gotten faster, but not terribly much
> quicker. there's been no significant change in latency between
> machines i've been paying attention to in various parts of the US
> (mostly east coast) and western europe (mostly London) for the past 4
> years. the bandwidth (and bandwidth/$) have both improved
> significantly.
>
> (this is not true for asia, especially india, where i've seen very
> significant improvements)
>