add support for root filesystem image transfer via uftp, and md5sum c…

[rich350]

This supercedes pull request #3545. I removed my changes from master, added branch rich350_uftp, and added my changes to this branch.

[xcatbot]

CI CHECK RESULT : > PR FORMAT WARNING : Missing milestone.Missing labels.> BUILD SUCCESSFUL > INSTALL XCAT SUCCESSFUL> CODE SYNTAX CORRECT> FAST REGRESSION TEST Successful: Totalcase 215 Passed 215 Failed 0

[immarvin]

how about -R -1?

       -R txrate
	      The  transmission	 speed	in Kbps.  Specifying -1 for this value
	      results in data being sent as fast as the network interface will
	      allow.   Using  a value of -1 is recommended only if the network
	      path between the server and  all	clients	 is  as	 fast  as  the
	      server's	local  interface, and works best in a gigabit environ-
	      ment.   Default is 1000 Kbps.  Ignored if -C is given any	 value
	      other than "none".

seems the block_size should be less than MTU,

       -b block_size
	      Specifies the size of a data block.  This value should be around
	      100-200 bytes less that the path MTU to provide ample  room  for
	      all  headers  and extensions, up to and including the IP and UDP
	      headers.	Prior to version 4.0, this option  specified  the  MTU
	      and calculated the block size based on that.  Default is 1300.

[rich350]

R -1 gives similar results:

-rw-r--r-- 1 root root 3541421170 Jul 28 22:12 /install/netboot/crest-compute/rhels7.3/20170726/rootimg.cpio.gz

uftp -I enP3p5s0f0 -R -1 -D /rootimg.cpio.gz /install/netboot/crest-compute/rhels7.3/20170726/rootimg.cpio.gz

Transfer status:
Host: 0xAC1ECC04 Status: Completed time: 32.555 seconds
Total elapsed time: 32.555 seconds
Overall throughput: 106231.95 KB/s

It would be interesting to see what happens when the sender has a 10Gb/s interface and the receiver has a 1Gb/s interface. I would say this would create buffer overflows on the switch, unless -R 950000 is used.

Regarding block size, it actually will work with -b 8800 and MTU=1500. Perhaps UDP fragmentation and continuation is handling this. In any event, I agree that block size should be less than MTU. Since most computes probably have a 1Gb/s interface, the safest setting would be default block size and -R 950000.

[immarvin]

hi @rich350 , what is this argument "delay|t=s" => \$uftpdelay for?

[rich350]

This is an amount of time to wait to make sure all booting nodes have gone through their hardware initialization, loaded the kernel and initrd, started xcatroot, and started uftpd. For example, let's say we are booting lots of nodes at the same time to the same image. Each node will initialize, but maybe a few nodes take longer to load a particular driver for whatever reason. So, with each boot there will be a fastest node, and a slowest node. The fastest node will start uftpd and be the first to send a request to uftp-listener for the image. If uftp-listener immediately starts the transfer after the first request, the slowest node might not have started uftpd yet, and would therefore miss the transfer. So, uftpdelay is the amount of time that uftp-listener should wait before starting the transfer, once it receives the first request from the node that booted the fastest.

Since there is a timeout built into the uftp transfer logic in xcatroot, both uftp-listener and xcatroot need to be aware of uftpdelay, so it is passed as a boot parameter. I added the timeout so that if some node is really slow and doesn't get uftpd started before the transfer starts, then sends his request after the transfer has started, it will time out and fall back to wget. The default of 30 seconds is probably overkill, and could probably safely be reduced to 15 or even 10 seconds, but this will depend on the particular hardware, networking, number of nodes, etc. Since this will vary by site, I went with a safe default that can be tuned.

[immarvin]

hi @rich350 , have you signed the CLA? http://xcat-docs.readthedocs.io/en/stable/developers/license/contributors.html

We can only accept your PR after you sign the CLA, thx

[rich350]

I should be on the corporate CLA for Oak Ridge National Laboratory (UT-Battelle). In case I'm not, I just sent an individual CLA as well. Thanks, Rich

…

On Tue, Jul 31, 2018 at 10:55 PM, yangsong ***@***.***> wrote: hi @rich350 <https://github.com/rich350> , have you signed the CLA? http://xcat-docs.readthedocs.io/en/stable/developers/ license/contributors.html We can only accept your PR after you sign the CLA, thx — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#3560 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ALNocyJ72vuiHGG6yd_d5GLnuTPta3HZks5uMRilgaJpZM4Om1_1> .

[whowutwut]

@rich350 Thanks! Yes, you are covered under the CCLA, just need to make that connection and tag your GitHub ID so we know, thanks. I'll discard the individual CLA