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Re: [CentOS] Mysql databases from old system?
by Les Mikesell 15 Nov '13

15 Nov '13

On Fri, Nov 15, 2013 at 12:32 PM, Reindl Harald <h.reindl(a)thelounge.net> wrote: > >> Yes, if you do things that work in general, you don't have to know all >> of the internals of every specific version of every specific program >> that you might ever touch. > > than better be quiet instead contradict and correct people with > generic wisdom which are on-topic and have the specific knowledge > and experience over many years Fine, the next time I want to move MySQL 4.0-4.5 on Apple OSX *Power PC* to MySQL 5.1/5.5 on Linux x86_64, I'll ask your advice. -- Les Mikesell lesmikesell(a)gmail.com

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Re: [CentOS] Mysql databases from old system?
by Les Mikesell 15 Nov '13

15 Nov '13

On Fri, Nov 15, 2013 at 12:00 PM, Reindl Harald <h.reindl(a)thelounge.net> wrote: > > and why did you strip the part where i googled for you the endianess > of MacOSX on PPC because i clearly statet mysql-data dirs used here > in production went from MySQL 3.x on Windows i686 over MySQL 4.0-4.5 > on Apple OSX *Power PC* to MySQL 5.1/5.5 on Linux x86_64? Because that has nothing to do with the generic issue of moving binary data from one CPU type to another. If you got lucky and something happened to work for you once, great. It's not something people should count on - especially for programs that provide a tool for portability and consistency. -- Les Mikesell lesmikesell(a)gmail.com

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Re: [CentOS] Mysql databases from old system?
by Les Mikesell 15 Nov '13

15 Nov '13

On Fri, Nov 15, 2013 at 10:58 AM, Reindl Harald <h.reindl(a)thelounge.net> wrote: > >> I don't know specifically about Mysql but pretty much anything that stores binary >> representations to disk needs to be converted. > > with this logic you would need to convert MS office files > containing embedded images too.... No, image formats have standardized binary representations so they are portable. The problem is with applications that write their own binary values and data structures to disk without conversion. I don't know much about msyql internals, but I wouldn't expect it to go to the trouble of normalizing things like index files just in case you wanted to move those disks to a sparc instead of doing a dump/load. -- Les Mikesell lesmikesell(a)gmail.com

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Expanding EVMS raid1 array
by Peter Crighton 15 Nov '13

15 Nov '13

I started with two 160GB drives in RAID1 using EVMS on Centos 4.4. Both drives have now been replaced with 320GB drives but naturally are only offering 160GB (they were replaced individually at different times and self-recovered as they were RAID1. I cannot work out how to increase the size of the array to use all the available space on the disk. If I understand correctly, I should unmount the array, deactivate it and select expand. The problem is that while I can unmount and deactivate it, there is nothing to expand (selecting expand volume, expand storage object and expand container all report no items found). Also, right clicking on the array (in EVMSGUI) doesn't have expand as an option. The disks are formatted in Ext2/3. Have I missed something? I'd rather not replace the old drives, create a second RAID array and copy all the data across as I've a feeling that I'll then have to reset permissions and shares (although I just might get away with then removing the original RAID array and mounting the new one in the same location). In my mind it also ought to be easier to simply re-size the array than have to set up new ones and move the data across. -- Peter Crighton

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Re: [CentOS] Mysql databases from old system?
by Les Mikesell 15 Nov '13

15 Nov '13

On Fri, Nov 15, 2013 at 10:01 AM, Reindl Harald <h.reindl(a)thelounge.net> wrote: > > abd what has the CPU type to do with the mysql datadir? Really??? You've never used processors with different bit/byte order than Intel's? I don't know specifically about Mysql but pretty much anything that stores binary representations to disk needs to be converted. > speaking with 10 years expierience and some hundret databases originally > created with MySQl 3.x on Windows, 4.x-5.0 running on MacOSX and since > MySQL 5.1 until now with 5.5 as well as MariaDB 5.5 running on Linux > without a single time payling around with dumps So no sparc's or the like in the picture? Not sure which way powerpc macs ran. -- Les Mikesell lesmikesell(a)gmail.com

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Mysql databases from old system?
by Timothy Murphy 15 Nov '13

15 Nov '13

Last week I had a hard disk failure on my CentOS server. I managed to re-install CentOS on a new disk. I have the old mysql databases from /var/lib/mysql . Can I just move them to my new disk? Any help or suggestions gratefully received. -- Timothy Murphy e-mail: gayleard /at/ eircom.net School of Mathematics, Trinity College, Dublin 2, Ireland

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First Time Setting up RAID
by James B. Byrne 15 Nov '13

15 Nov '13

Arch = x86_64 CentOS-6.4 We have a cold server with 32Gb RAM and 8 x 3TB SATA drives mounted in hotswap cells. The intended purpose of this system is as an ERP application and DBMS host. The ERP application will likely eventually have web access but at the moment only dedicated client applications can connect to it. I am researching how to best set this system up for use as a production host employing RAID. I have read the (minimal) documentation respecting RAID on the RedHat site and have found and read a few online guides. Naturally, in my ignorance I have a bunch of questions to ask and I probably have a bunch more that I should but do not know enough yet to ask. >From what I have read it appears that the system disk must use RAID 1 if it uses RAID at all. Is this the case? If so, is there any benefit to be had by taking two of the 8 drives (6Tb) solely to hold the OS and boot partition? Should these two drives be pulled and replaced with two smaller ones or should we bother with RAID for the boot disk at all? Given that one or two drive bays will be given over to the OS what should be the configuration of the remaining six? It appears from what I have read that RAID 5 is the only viable option. It also appears that the amount of storage available on a RAID5 array with N members is N-1/N. I also read that as the number of members increase both latency and the risk of data loss increases. As the amount of disk space we have in this unit (24Tb) is greater than the total storage of all our existing hosts it appears that a RAID5 array of 5 units would leave at least one hot spare in the chassis and two if the OS is put on one disk. Alternatively, the thought comes to mind that we could do a RAID1 with two RAID5 arrays each of which have 3 drives. Whether one would actually want to do that seems to me a bit questionable but it seems to be at least possible. Comments, suggestions, caveats? Regards, -- *** E-Mail is NOT a SECURE channel *** James B. Byrne mailto:ByrneJB@Harte-Lyne.ca Harte & Lyne Limited http://www.harte-lyne.ca 9 Brockley Drive vox: +1 905 561 1241 Hamilton, Ontario fax: +1 905 561 0757 Canada L8E 3C3

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Re: [CentOS] First Time Setting up RAID
by James B. Byrne 14 Nov '13

14 Nov '13

On Thu, November 14, 2013 12:51, Reindl Harald wrote: > > > Am 14.11.2013 18:23, schrieb James B. Byrne: >> From what I have read it appears that the system disk must use RAID 1 if it >> uses RAID at all. > > no! > > /boot must be RAID1, see below > md0: /boot > md1: / > md2: /data > > [root@srv-rhsoft:~]$ cat /proc/mdstat > Personalities : [raid1] [raid10] > md2 : active raid10 sda3[4] sdb3[3] sdc3[5] sdd3[0] > 3875222528 blocks super 1.1 512K chunks 2 near-copies [4/4] [UUUU] > bitmap: 4/29 pages [16KB], 65536KB chunk > > md1 : active raid10 sda2[4] sdb2[3] sdc2[5] sdd2[0] > 30716928 blocks super 1.1 512K chunks 2 near-copies [4/4] [UUUU] > bitmap: 0/1 pages [0KB], 65536KB chunk > > md0 : active raid1 sda1[4] sdb1[3] sdd1[0] sdc1[5] > 511988 blocks super 1.0 [4/4] [UUUU] > So, this is saying, if I read it aright, that one can have multiple RAID arrays spread over the same spindles but each in differing partitions. Is that right? I am just getting started with this so I am trying to fit what I am reading regarding RAID with what I have dealt with in the past, mainly LVM ext3 volumes. So I am doubtless just not getting it in some important way. BTW, I intend to install CentOS-6.4 with software RAID as the eight disks are mounted in the system chassis. As far as I can tell, there is no hardware RAID controller (unless there is one on the MB, in which case SW Raid is likely a better choice anyway. Regards, -- *** E-Mail is NOT a SECURE channel *** James B. Byrne mailto:ByrneJB@Harte-Lyne.ca Harte & Lyne Limited http://www.harte-lyne.ca 9 Brockley Drive vox: +1 905 561 1241 Hamilton, Ontario fax: +1 905 561 0757 Canada L8E 3C3

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Problem with X11 application and Nouveau driver
by Glenn Eychaner 14 Nov '13

14 Nov '13

I have finally received and am configuring my new workstations eith the NVS510 graphics cards, and have run into rather a problem. The X server seems to be loading the NOUVEAU driver properly (based on the contents of Xorg.0.log), but I have one X11 application that doesn't work correctly; it runs as though XSynchronized is always True, even though it's explicitly set to False in the code. In other words, its redraw behavior is god-awful; worse because it auto-redraws once per second for little apparent reason. And some of the windows draw with artifacts if they're covered and uncovered. Any ideas, anyone? I will gladly provide more info on request, but I'm not an expert X11 programmer (worse, this application uses a third party wrapper library). This is definitely new behavior on this new computer (the previous computers, also using the Nouveau driver with GeForce 7600 cards, did not seem to have this behavior). -G. -- Glenn Eychaner (geychaner(a)lco.cl) Telescope Systems Programmer, Las Campanas Observatory

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Re: [CentOS] NFS hard mount
by Denniston, Todd A CIV NAVSURFWARCENDIV Crane 14 Nov '13

14 Nov '13

> -----Original Message----- > From: Rita [mailto:rmorgan466@gmail.com] > Sent: Tuesday, November 12, 2013 7:22 PM > To: CentOS mailing list > Subject: Re: [CentOS] NFS hard mount > > Yes, unmount the share and error to the client app. > Sounds like you want to have a combination of mounting with the intr flag[1] and use autofs[2] so that the file system is not mounted ALL the time, but not so soft as to loose data all the time. I have seen soft loose data reliably, were in the same environment (and same equipment) hard,intr does not loose data. My experience is that intr is useful in situations where servers go down/have link issues frequently, and autofs with short timeouts (~15s < timeout <~60s) makes those issues even less _visible_. It will not get you an automatic unmount of the share and error to the client app in the case of server down, but it will /allow/ you to terminate the client and unmount as needed IIRC. [1] nfs mounting page with thanks to zGreenfelder https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux… [2] autofs page https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux… > > > On Tue, Nov 12, 2013 at 6:25 PM, John R Pierce <pierce(a)hogranch.com> wrote: > > > On 11/12/2013 3:18 PM, Rita wrote: > > > Is there a tunable to set NFS hard mount time out? For instance, if the > > > server becomes unavailable for extended amount of time, say 1 hour. I > > would > > > like to timeout after 30 secs. > > > > timeout and do what, unmount the share, and error to the client app > > thats trying to do a read(),write(),open(),stat(),etc ? > > > > > > > > -- > > john r pierce 37N 122W > > somewhere on the middle of the left coast > > > > _______________________________________________ > > CentOS mailing list > > CentOS(a)centos.org > > http://lists.centos.org/mailman/listinfo/centos > > > > > > -- > --- Get your facts first, then you can distort them as you please.-- Even when this disclaimer is not here: I am not a contracting officer. I do not have authority to make or modify the terms of any contract.

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