Regulate NIC speed ( Bandwidth )

[kaushikbr]

Hi,

Is it possible to control/regulate the network bandwidth on HP-UX ?

Thanks in advance for all your suggestions.
Regards
Kaushik

[Steven E. Protter]

Shalom,

As in regular individual users bandwidth?

I'd say probably not. The open source programs that permit you to do this on Linux would require extensive porting to work on HP-UX.

If I've not answered your question, please clarify your needs and I or others will respond.

SEP

[Peter Godron · Accepted solution]

Hi,
you can try an alter the setup of the NIC.
You can disable auto-negotiate, and use ladmin -S to mod the speed. Root access required.

Please give more info for better answer.

[kaushikbr]

Hi Protter,Peter
Thanks for your replies.

We have Oracle dataguard configured at the customers site. And the bandwidth between the Primary and the DR site is 30 MBPs.

However the network speeds on the test environment is about 100MBPs. We would like to do some tests with similar setup, in terms of network bandwidth. To verify if Dataguard can cope with it also to determine how long it takes to setup the standby database. The delay factor etc.

I'm looking for some method wherein I can reduce the network bandwidth b/w two identified test machines to 30MBPs.

Thanks and regards
Kaushik

[Steven E. Protter]

Shalom,

You can use lanadmin on a 100 BaseT card and step it down to 10 BaseT speeds. You can also change from full duplex to half duplex.

But setting a specific speed other than that will probably fail and result in no networking.

If you are using a 1000 BaseT cards, they only work autonegotiate. To regulare overall bandwith you'll probably need to play with switch configuration, which is both problematic, and more likey to end all networking rather than achieve your goal.

SEP

[Peter Godron]

Hi,
ok, another suggestion:
What would happen if rather than restrict the bandwidth you increase the datavolume?

If you run a number of ftp processes at the same time, over the same route, you should see a reduction in available bandwidth.

A looped parallel transfer of a large file may do.

Also, speak to your network admin people, they may have methods already !

[Yogeeraj_1]

hi Kaushik,

you can also try to bring in "slow" devices (hub/switch) that would restrict the bandwidth to the server.

if you have multiple network interface cards, this will be the wisest solution to adopt.

kind regards
yogeeraj

[rick jones]

I've no idea if the code is still "good" but under:

ftp://ftp.cup.hp.com/dist/networking/tools/

there is a port of the BSD "dummynet" code to a STREAMS module one can push onto the stack in HP-UX. Depending on where that is pushed into the stream, you can either limit an entire NIC, or specific connections to a specific bitrate. You can also introduce delay and loss.

It isn't a "product" so it isn't "supported" but there are a couple folks who might be able to answer questions. It isn't exactly the cheapest thing in the world wrt CPU consumption. Whenever I've used it in the past, I've used it on the load generators rather than the system under test/benchmark.

I suppose you might also look into what ipfilter can do - I don't know that it has rate limiting features and delay and such, but who knows. It is supported and should have documentation on http://docs.hp.com/

Finally, if all else fails, you could stick a linux or bsd box between your system and the rest of the world and run some of the BW limiting stuff there.

[Hein van den Heuvel]

What is the distance to the DR site?
I know of a DR site setup (in Holland) where 100 MB/sec was available, but the distance was 70 KM (50-ish miles). So due to the old speed of light limitation (300,000 KM/sec = 300 KM/millisecond) they need about 1/2 millisecond for data + ack.
That upperbound was much more critical to them than the MB/sec.
The HP OpenVMS Lab (and others) used to test this using a 100km spool of glass. These days they have an electronic device injecting the delay. Sorry, don't know the manufacture but could find out. I would expect such toy to also be able to reduct MB/sec artificially.

Sounds like MB/sec is you main concern, so the main - DR network latency might not be an issue.

fwiw,
Hein,