perfSONAR User Q&A and Other Discussion

[Gerry Creager - NOAA Affiliate <>]

What I've had to do with RedHat (or, more precisely, CentOS and Scientific Linux) is to create the system on the relatively small SSDs, which I mirrored, then add the spinning media later, create an LVM for it, and incorporate it in, and mount /var... and for me, /home... on spinning media. The two-step process is a pain, but do-able. And, I get a machine that reboots, taking advantage of the fast SSDs, but also having the lifetime of the spinning hard disks.

RedHat hasn't made it particularly easy.

On Mon, Aug 19, 2013 at 12:38 PM, David Mitchell <> wrote:

If we choose 'replace existing Linux system' rather than 'Use entire drive' will CentOS leave the partitions intact? I was hoping to do ps.ncar.xsede.org this week so I'm definitely interested in the preferred route.

-David

On Aug 19, 2013, at 11:31 AM, Kathy Benninger <> wrote:

> Hi Aaron,
>
> Available storage devices are:
>  one ~220GB SSD
>  two 2TB disks
> I told RedHat to use all the storage for perfSONAR.
>
> RedHat configured:
>  ~64GB (about 1/3 of the SSD) for /, /dev/shm, and /boot
>  ~4TB for /home
> resulting in database and log storage all configured onto a portion of the (relatively) small SSD.  The software RAID is gone, with all 4TB allocated to /home.
>
> In detail, I ended up with:
>
> Filesystem           1K-blocks      Used Available Use% Mounted on
> /dev/mapper/vg_dhcp145c-lv_root
>                      51606140   2098480  46886220   5% /
> tmpfs                 12298336         0  12298336   0% /dev/shm
> /dev/sda1               495844     37930    432314   9% /boot
> /dev/mapper/vg_dhcp145c-lv_home
>                     4012173384    199824 3808166840   1% /home
>
> When what I really want is what I had before:
>
> Filesystem           1K-blocks      Used Available Use% Mounted on
> /dev/sda2            119031092   1906408 110980628   2% /
> /dev/sda6              4956284    141252   4559200   4% /tmp
> /dev/md0             1892332848  61523772 1733133480   4% /var
> /dev/sda3             49594228   2110072  44924200   5% /home
> /dev/sda1               988088     46128    890956   5% /boot
> tmpfs                  1548864         0   1548864   0% /dev/shm
>
> I'm open to suggestions on how to proceed.  ideas other than removing the SSD from the perfSONAR device list and just doing a 4TB install on the two disks?
>
> Kathy
>
>
> On 8/19/2013 8:33 AM, Aaron Brown wrote:
>> Hey Kathy,
>>
>> Unfortunately, yes. RedHat has started to decrease the kickstart
>> functionality a bit, and the most noticeable thing now has been the disk
>> partitioning, or lack thereof. That said, how RedHat decide to partition
>> things? Everything on one of the RAID-1 disks?
>>
>> Cheers,
>> Aaron
>> On Aug 16, 2013, at 12:41 PM, Kathy Benninger <> wrote:
>>
>>> Is it the case that there is no longer an option to manually configure
>>> the disk storage on a pS-PT 3.3 node?
>>>
>>> I think there was a thread to that effect, but I can't find it and want
>>> to confirm before I settle with the configuration it wants to give me.
>>>
>>> (My wish was to restore booting and home directories to an SSD and set
>>> /var primary database storage to a software-mirrored RAID1, but I can't
>>> figure out how to do that.)
>>>
>>> Except for the unfortunate disk partitioning, the backup/restore and
>>> upgrade appear to have worked as expected.
>>>
>>> Kathy
>>>
>>> --------------------------
>>> Kathy Benninger
>>> Pittsburgh Supercomputing Center
>>
>>

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| David Mitchell ()       Network Engineer IV  |
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Gerry Creager

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