Connect 2 hosts with fiber

[Larry Basford]

Is it possible to Zone 2 hosts together for the purpose of transfering lots of data faster ?
I've done it with 100MB/turnover cable.
Can it be done with fiber?
lots like 50-80GB
Direct route
Going from an HP to an IBM
tar -cvf - 80GBdir| remsh RS_node "(cd /data; tar -xvf -)"

[Jean-Yves Picard]

Hello,

this sounds right, but depending on your fiber swicth, you might net get any significant increase.

you might get significant increase by removing the '-v' option in tar (unless you have very few files)

Jean-Yves Picard

[RAC_1]

I do not think you can have something like fibre turnover cable. You will have get FC HUB and FC cards to do that.
Also when doing following keep in mind that, HP tar understands only 10KB. so on IBM, you will have to tell IBM tar to get 10KB.

tar -cvf - 80GBdir| remsh RS_node "(cd /data; tar -xvf -)"

Should be modified as follows.

tar -cvf - 80GBdir| remsh RS_node "(cd /data; tar -xv -b 10 -f -)"

[Vladimir Fabecic]

Do not know about IBM machines, but I have done it with HP machines.
You can also create special VLAN with just two ports if using CISCO switch.
But crossover (turnover) cable is better solution.

[Steve Lewis · Accepted solution]

I did it last year between 2 npars on my Superdome using 1000-base SX fibre. Just turn over one end. Configure the interfaces, host equivalence and routes, then you are away. Remember to specify the correct remote host name (or use the private lan IP address directly.

Without a switch you can also set the MTU on each interface to 9000 (jumbo frames), not that that makes much difference to transmission rates on a fast server.

Tar is not the fastest method, but it does give you some cross-platform compatibility. However, remember the 32bit/2Gb file size limit! You may need 64 bit gtar.

[Larry Basford]

RAC,
I don't believe this is true.
HP man for tar says
b Use the next arg argument as the blocking factor for archive
records. The default is 20; the maximum is at least 20.
However, if the f - modifier is used to specify standard
input, the default blocking factor is 1.

IBM man tar has default and max 20 and
For output to ordinary files with the -f flag, you can save disk space by using a blocking
factor that matches the size of disk blocks (for example, the -b4 flag for 2048-byte disk
blocks).
But this does tranfer faster.
tar -cf - 80GBfile|remsh ibm2 "(cd /data;tar -x -b4 -f -)"

Vladimir,Steve, You have done this! Was it faster? And how do you configure the interfaces?

Compatibility is the big issue. I have 9 80GB IBM filesystems I need to present to the HP server. The tar is just a start.
NFS mount seems the only answer so far.

[Vladimir Fabecic]

Was it faster? We did some metrics and it was faster, but just a little bit. Logicaly, it must be faster because you do not have problem with network switch latency.
How was the interface configured? Speed 1000 bps and MTU 9000 (jumbo frames) each.
If I had your problem, I would also choose NFS because tar has to be used. Without need of tar I would choose ftp or rcp.

[Andy Torres]

As a remote option, you might consider a hyper fabric connection if you really need a permanent link between two hosts, like in an Oracle RAC cluster. It's an expensive option if you're just trying to transfer some files occasionally, as it requires new hardware and has its own learning curve. Just thought I'd drop that out there.

[Vladimir Fabecic]

Andy,
hyper fabric connection going from an HP to an IBM?
That is not possible!
Even in TRU64 cluster gigabit ethernet is OK as cluster interconnect for Oracle RAC.

[Andy Torres]

Sorry, didn't mean to confuse. I missed the "HP to IBM" part of the equation. Would they be able to talk to each other at all if they were connected over a HF switch?

[Alzhy]

Larry,

I did this On Solaris machines where there is support for running IP over Fibre-Channel and it worked great. Plumbing iP over 2G-FC esentialy gives you a 2Gbit network pipe.

I am not just sure if HP-uX and AIX has support for running IP over FC intrfaces.

I can suggest you also try using cross-over Gigabit connection -- IF both your HP and IBM machines have 'em.

[Larry Basford]

Thanks for all of the responses.
It looks like we will be going from an HP shop to an IBM shop due mostly to requirements and cost.
looking at IBM550Q or IBM570 for expandability HP just does not have a cost competitive product in the high midrange market.
570 to rx4640 rx7620

We need an 8 processor expandable to 16
It looks like IBM is going to win this one.