Thanks John, I'll give it a try and see what comes of it.
Richard Andrews Systems Administrator - IT Operations Pelmorex Media Inc. > -----Original Message----- > From: [email protected] [mailto:linux-poweredge- > [email protected]] On Behalf Of [email protected] > Sent: Tuesday, July 13, 2010 1:00 PM > To: [email protected] > Subject: Linux-PowerEdge Digest, Vol 73, Issue 21 > > Send Linux-PowerEdge mailing list submissions to > [email protected] > > To subscribe or unsubscribe via the World Wide Web, visit > https://lists.us.dell.com/mailman/listinfo/linux-poweredge > or, via email, send a message with subject or body 'help' to > [email protected] > > You can reach the person managing the list at > [email protected] > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Linux-PowerEdge digest..." > > > Today's Topics: > > 1. amazon ec2 hosting? (Doug Simmons) > 2. RE: Optimizing disk i/o performance (John LLOYD) > 3. Re: amazon ec2 hosting? (Simon Waters) > 4. OMSA & Suse Enterprise 11 (Ryan Kish) > 5. ssh nologin DRAC 4/P (Benito Lopera) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Tue, 13 Jul 2010 10:28:50 -0500 > From: "Doug Simmons" <[email protected]> > Subject: amazon ec2 hosting? > To: <[email protected]> > Message-ID: > <797303b748c24d40abdccc6416e356a403094...@libsrvxch2.cd.ds.siu.edu> > Content-Type: text/plain; charset="us-ascii" > > We're basically a poweredge shop, or are becoming so as the sun > equipment ages. But, it has been proposed that we consider cloud options > going forward. After an extensive research session spanning all of > fifteen or twenty minutes, I'm not sure we'd save much going to hosted > virtual instances and storage like with Amazon EC2. > > > > Do any of the list members have any experience with this service? > > > > Thanks, > > > > Doug Simmons > > Procedures and Systems Analyst II > > Morris Library Systems > > SIUC > > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: http://lists.us.dell.com/pipermail/linux- > poweredge/attachments/20100713/874df4ea/attachment-0001.htm > > ------------------------------ > > Message: 2 > Date: Tue, 13 Jul 2010 08:31:52 -0700 > From: John LLOYD <[email protected]> > Subject: RE: Optimizing disk i/o performance > To: "[email protected]" <[email protected]> > Message-ID: > <[email protected]> > Content-Type: text/plain; charset="us-ascii" > > > Date: Tue, 13 Jul 2010 10:40:06 -0400 > > From: Richard Andrews <[email protected]> > > Subject: Optimizing disk i/o performance > > To: "'[email protected]'" <[email protected]> > > Message-ID: > > <496a9f867c284a47a25bf0fb1a1ef81930dc7d0...@exchange-mb- > > 01.office.pelmorex.com> > > > > Content-Type: text/plain; charset="us-ascii" > > > > Hello, > > > > I'm investigating the most ideal settings to improve the performance of > > a glusterfs implementation. Are there optimal settings for the > > following parameters with respect to the Perc 6/I rev.122 controllers? > > > > /sys/block/sda/queue/nr_requests > > Blockdev Readahead value (blockdev -getra /dev/sda) > > > > Currently the default values for CentOS are 128 and 256 respectively. > > I understand that increasing nr_requests will have a memory usage > > impact and changing the readahead parameters may have a memory usage > > impact. > > > > Regards, > > > > Richard Andrews > > Pelmorex Media Inc. > > > > we typically setup a blockdev --setra of about 4k or 8k blocks per > physical device. memory is cheap. It usually makes a better-than-50% > improvement in IO of large files. > > Here is an example. sdb is a 6-way raid set, so it gets 1k per disk. > This is a SLES10 system. RH/CentOS may vary in where or how you do this. > > # cat /etc/init.d/boot.local > #! /bin/sh > > blockdev --setra 4096 /dev/sdc > blockdev --setra 4096 /dev/sde > blockdev --setra 4096 /dev/sdf > blockdev --setra 4096 /dev/sdg > blockdev --setra 4096 /dev/sdh > blockdev --setra 4096 /dev/sdi > > blockdev --setra 6144 /dev/sdb > > echo noop > /sys/block/sdc/queue/scheduler > echo noop > /sys/block/sde/queue/scheduler > echo noop > /sys/block/sdf/queue/scheduler > echo noop > /sys/block/sdg/queue/scheduler > echo noop > /sys/block/sdh/queue/scheduler > echo noop > /sys/block/sdi/queue/scheduler > > > Resetting the scheduler means that Linux and the RAID controller are not > competing for who has the best IO scheduler. Since you cannot turn off > RAID controller scheduling (except by avoiding RAID) we keep Linux out of > the picture. > > > --John > > > > > > ------------------------------ > > Message: 3 > Date: Tue, 13 Jul 2010 17:29:15 +0100 > From: Simon Waters <[email protected]> > Subject: Re: amazon ec2 hosting? > To: [email protected] > Message-ID: <[email protected]> > Content-Type: text/plain; charset="utf-8" > > On Tuesday 13 July 2010 16:28:50 Doug Simmons wrote: > > > > Do any of the list members have any experience with this service? > > We are pondering a different cloud system based on XEN offering similar on > a > smaller scale than Amazon. Pricing is slightly cheaper, but not much in > it. > They charge for disk I/O bandwidth which required some quick checks on > what > we do, perils of expensive external storage systems. > > In our case we've done a little more than 20 minutes research, but the > conclusions aren't clear cut. > > I think the motivation for moving to a cloud system is probably not solely > financial, one has to expect that the option to migrate instances will add > robustness, the option to add systems flexibility, and the scalability are > the factors one is looking for. Also these systems have large robust > storage > systems which are beyond the pockets of most businesses. > > My concern still is availability. Amazon EC2 I hear good things about. A > couple of other providers we looked at are not bad, most don't have a > track > record you could point at and think "that is better than a decent hosting > provider" and dedicated hardware - we routinely get 1 year plus uptimes on > DELL hardware boxes that are a decade old - when we see top cloud > providers > off air for a couple of days at a time it doesn't convince me. > > I've yet to use a virtualization product that didn't have > virtualization "bugs", i.e. errors, downtime, or problems due to the > virtualization process. The OpenVZ stuff we tried didn't memory map files > correctly, one provider using XEN migrated our instance to different > hardware > for maintenance and when it woke up milliseconds later it was 1914 > (Postfix > said it wasn't doing anything till the date was plausible - which was > probably wise - but did nothing for availability). What I've read of EC2 > is > that it is rather idiosyncratic compared to more recent virtualization > offerings elsewhere, on the other hand they seem to have been free of > major > problems for a while. > > The XEN provider we've looked at most closely seem promising, they seem to > have resolved a lot of issues with their earlier system, but I have > concerns > at scalability because they limit the available RAM to each instance > somewhat > and when you have hundreds of gigabytes of data it would be nice to know > you > could scale RAM to something more substantial if needed, and serious disk > space is expensive in these storage arrays. And they have zero track > record > on their new system because it is new. On the other hand I'm not THAT > scared > of virtualization just want to test it the whole way, which is time > consuming. > > One provider looked solid, but the pricing was high, and the > marketing/emphasis was all to hosting enterprise servers rather than web > servers (which is what we want). > > Anyone gone with a dual provider strategy - where they create instances at > different cloud providers, and fail across on long outages? As that would > address my key concerns about reliability, but it looks expensive and > complex > to implement. > > If there were relatively cheap network storage systems around with > suitable > characteristics I'd be tempted to build our own XEN hosting system to get > the > advantages of virtualisation without the pain of a third party > relationship. > But I haven't read that bit of 'the Book of XEN' yet, and suspect the > answer > is "no". > > > > ------------------------------ > > Message: 4 > Date: Tue, 13 Jul 2010 10:47:26 -0600 > From: "Ryan Kish" <[email protected]> > Subject: OMSA & Suse Enterprise 11 > To: <[email protected]> > Message-ID: > <[email protected]> > Content-Type: text/plain; charset="us-ascii" > > Hi, > > I am trying to track down OMSA packages for SLES 11 (i386). > Unfortunately, it appears the only packages available are x86_64. Does > anyone know where I can obtain OMSA for SLES11 on i386? > > Thanks! > Ryan > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: http://lists.us.dell.com/pipermail/linux- > poweredge/attachments/20100713/0235efda/attachment-0001.htm > > ------------------------------ > > Message: 5 > Date: Tue, 13 Jul 2010 18:53:18 +0200 > From: Benito Lopera <[email protected]> > Subject: ssh nologin DRAC 4/P > To: [email protected] > Message-ID: > <[email protected]> > Content-Type: text/plain; charset="iso-8859-1" > > Hi, i have a problem with the ssh access on the DRAC of my dell R200 > servers. I have a script to make a soft shutdown doing "stop system1" en > the > DRAC shell, but the problem is sometimes the DRAC denied the ssh enter. > For > example: > > r...@local# ssh -l root 192.168.0.23 > [email protected]'s password: > > Dell Remote Access Controller 4/P (DRAC 4/P) > Firmware Version 1.71 (Build 02.19) > [root]# exit > > Connection to 192.168.0.23 closed. > r...@local# > > Everything is OK, but i try 2 min later and this is the result: > > r...@local# ssh -l root 192.168.0.23 > Received disconnect from 192.168.0.23: 11: Logged out. > r...@local# > > The password is the same in both cases. I read on the manual that only one > SSH session is supported at any given time but i know that nobody is > logged > in, somebody knows the cause of this problem? > > Thanks. > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: http://lists.us.dell.com/pipermail/linux- > poweredge/attachments/20100713/7352546c/attachment-0001.htm > > ------------------------------ > > _______________________________________________ > Linux-PowerEdge mailing list > [email protected] > https://lists.us.dell.com/mailman/listinfo/linux-poweredge > Please read the FAQ at http://lists.us.dell.com/faq > > End of Linux-PowerEdge Digest, Vol 73, Issue 21 > *********************************************** _______________________________________________ Linux-PowerEdge mailing list [email protected] https://lists.us.dell.com/mailman/listinfo/linux-poweredge Please read the FAQ at http://lists.us.dell.com/faq
