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centos 6 - 1 of 2 machines starts and not the other
by fakessh ＠ 24 Feb '12

24 Feb '12

hu guys I regularly read this list I can usually find me in the excellent documentation apache. I'm in front of a very strange problem I possess two desktop machines which works with the Apache server with centos 6 1 of 2 machines starts and not the other. I use the apache config file here that provides standard distribution any help for me sincerely -- http://pgp.mit.edu:11371/pks/lookup?op=get&search=0xC2626742 gpg --keyserver pgp.mit.edu --recv-key C2626742 http://urlshort.eu fakessh @ http://gplus.to/sshfake http://gplus.to/sshswilting http://gplus.to/john.swilting https://lists.fakessh.eu/mailman/ This list is moderated by me, but all applications will be accepted provided they receive a note of presentation

3 5

Really bad KVM disk performance
by Bob Puff 23 Feb '12

23 Feb '12

Hi Gang, I recently rented a server at a datacenter with Centos 5.7 X64, Q9550 Processor, 8GB Ram, and dual 250GB SATA HDs (with 16mb cache). They had loaded it with KVM, and installed a 30-day trial of Virtualizor as the front-end for KVM. I was so impressed with how fasts the guests ran that I want to build a few of these machines for myself. I just installed one: same Q9550 processor, 4GB ram, and dual 250GB SATA HDs (with 32mb cache). I installed Centos 6.2 X64, and installed Webmin's Cloudmin as the front-end. Immediately when I was installing stuff, I could tell this new system I just built was not nearly as fast as the first one. I ran some CPU and disk benchmarking programs, and saw that while the CPU stuff tested similarly, the disk thruput was much different... Down-right poor in one of the guests! On both systems, /dev/md2 is a LVM reserved exclusively for KVM guests. So each guest is running in its own logical volume, in software raid. Thinking there may be something wrong with the HDs, I ran Bonnie ( http://www.coker.com.au/bonnie++/ ) and compared both host machines. They tested fairly similar (within 10%). Yet comparing their guests is like night and day. Example: On good machine's Centos 5.7 x32 guest install: # hdparm -tT /dev/hda /dev/hda: Timing cached reads: 26760 MB in 1.99 seconds = 13417.10 MB/sec Timing buffered disk reads: 388 MB in 3.01 seconds = 128.86 MB/sec On my machine's Centos 5.7 x32 guest install: # hdparm -tT /dev/hda /dev/hda: Timing cached reads: 1864 MB in 2.16 seconds = 863.87 MB/sec Timing buffered disk reads: 358 MB in 3.08 seconds = 116.17 MB/sec On one of my machine's Mandrake 8.2 x32 guest install: # hdparm -tT /dev/hda /dev/hda: Timing buffer-cache reads: 27000 MB in 2.00 seconds = 13500.00 MB/sec Timing buffered disk reads: 12 MB in 3.66 seconds = 3.28 MB/sec On that system, the hdparm's -i output shows: # hdparm -i /dev/hda /dev/hda: Model=QEMU HARDDISK, FwRev=0.12.1, SerialNo=QM00001 Config={ Fixed } RawCHS=16383/16/63, TrkSize=32256, SectSize=512, ECCbytes=4 BuffType=DualPortCache, BuffSize=256kB, MaxMultSect=16, MultSect=16 CurCHS=16383/16/63, CurSects=16514064, LBA=yes, LBAsects=73400320 IORDY=yes, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120} PIO modes: pio0 pio1 pio2 DMA modes: sdma0 sdma1 sdma2 mdma0 mdma1 mdma2 UDMA modes: udma0 udma1 udma2 udma3 udma4 *udma5 AdvancedPM=no Drive conforms to: ATA/ATAPI-5 published, ANSI NCITS 340-2000: * signifies the current active mode The bonnie numbers show for sequential output: Good Machine Host: 76,857K/Sec My Machine Host: 72,561K/Sec Good Machine Centos 5.7 Guest: 66,266K/sec My Machine Centos 5.7 Guest: 20,623K/sec My machine Mandrake Guest: 1,365K/sec Where should I look? I realize I do have two different front-ends to KVM, and perhaps they are passing different parameters to it. I am also running the KVM from Centos 6.2 on my machine, vs the other server is running on 5.7, but I would have thought that "newer is better". Also note that my hard drives have a larger cache. On a side note, I'm not thrilled with the Virtualizor's tech support, but the product seems easy to use, once it actually works. Cloudmin seems to be buggy, and not let you do things like change cd images on the fly, access the console before the machine fully boots (!)... Any suggestions on other, preferably open-source options? I'm a definite newbie to this virtualization stuff. Bob

5 4

System reboots automatically more or less every two days
by fabio.pugnaghi＠tiscali.it 23 Feb '12

23 Feb '12

Good Evening, I have a problem with CentOS 6.2. On December 2011 I installed CentOS 6.1 on a HP ProLiant DL 165 G7 server. Recentely I upgraded to CentOS 6.2 but at reboot the system didn't startup. So I removed new kernel kernel-2.6.32-220.4.2.el6 and CentOS was again able to startup with original kernel-2.6.32-71.el6.x86_64. But now every two days the system automatically reboots as you can see below: reboot system boot 2.6.32-71.el6.x8 Wed Feb 22 22:53 - 17:10 (18:16) reboot system boot 2.6.32-71.el6.x8 Wed Feb 22 20:04 - 17:10 (21:06) reboot system boot 2.6.32-71.el6.x8 Fri Feb 17 22:55 - 17:10 (5 +18:14) reboot system boot 2.6.32-71.el6.x8 Fri Feb 17 07:05 - 17:10 (6 +10:04) reboot system boot 2.6.32-71.el6.x8 Wed Feb 15 15:02 - 17:10 (8 +02:08) reboot system boot 2.6.32-71.el6.x8 Mon Feb 13 00:33 - 17:10 (10 +16:36) reboot system boot 2.6.32-71.el6.x8 Sun Feb 12 16:08 - 17:10 (11 +01:02) reboot system boot 2.6.32-71.el6.x8 Sun Feb 12 15:00 - 17:10 (11 +02:09) reboot system boot 2.6.32-71.el6.x8 Thu Feb 9 18:06 - 17:10 (13 +23:03) reboot system boot 2.6.32-71.el6.x8 Tue Feb 7 01:22 - 17:10 (16 +15:47) In log file /var/log/messages there are no particular events happened before system halt down. Have you some idea of how I can resolve these problems? Do you think they are correlated? Thank you for the attention. Fabio E' nata indoona : chiama, videochiama e messaggia Gratis. Scarica indoona per iPhone, Android e PC

6 8

Re: [CentOS] Please I'd like to install 2 websites on my un managed VPS on CentOS6
by Wuxi Ixuw 23 Feb '12

23 Feb '12

I'd like to learn indeed but feel like lost in a very big ocean. please if you may give any outline that would be awesome or even a title for a good book to start with. On 23/02/2012 09:15 PM, Reindl Harald wrote: > and where is the difference between a real server and a VPS > in the context of a webserver -> hint: there is none! > > you have two choices: > > * read many manuals and learn the needed things > * to not use VPS at all and switch to a maintained hosting > > there is no easy way for " i have no technical knowledge but i > want to have simple instructions for making a secure root-server" > > if you have not the knowledge, not the time to learn > and not the money to let do people who can simply > do not such things! > > Am 23.02.2012 20:05, schrieb Wuxi Ixuw: > > Please suggest a one as I am keep goggling and all result bring books > dealing with linux as a real server and not a vps. > > On 23/02/2012 07:01 PM, Les Mikesell wrote: > >> On Thu, Feb 23, 2012 at 7:19 AM, Wuxi Ixuw<w7u64xi7(a)gmail.com> wrote: >>> I am afraid if I get hacked and do not know what should i do to setup >>> the whole vps the right way. >> There are many large books on the subject. If you don't want to spend >> your life staying ahead of the game: >> Use popular software >> Don't change defaults you don't understand >> Keep it up to date >> Use good passwords >> > _______________________________________________ > CentOS mailing list > CentOS(a)centos.org > http://lists.centos.org/mailman/listinfo/centos > >

1 0

ViSpan
by Steve Campbell 23 Feb '12

23 Feb '12

I was looking for the old Vispan stuff, and it seems to have disappeared from the web. Now I realize it was old, but it did provide some details that I liked on my old servers. I've got mailscanner-mrtg running, but that only provides a view of what mailscanner sees. Does anyone know of a good replacement for vispan that might give complete stats on what the mail server is doing instead of just what MailScanner is doing? thanks steve campbell

5 8

Ways To Practice Breaking My System?
by Alex Walker 23 Feb '12

23 Feb '12

Hi All I've been looking into some ways to break a CentOS system so I can perform some simulated disaster recovery and get some hands-on practice with rescue mode and other system recovery tools. I'm thinking to start off with things like corrupting the password file with random characters, breaking grub.conf. I've been doing some research on the net, but would welcome any input from list members. Does anybody have any creative suggestions for ways to break the CentOS boot process? Thanks in advance :) Alex.

11 13

CentOS 6.2 install problem squid winbind
by Mark Orenstein 23 Feb '12

23 Feb '12

In the install process, I checked squid and winbind. Squid access to winbind fails because squid was not added to the wbpriv group. I suspect that winbind is being installed after squid. I manually added squid to wbpriv in group and gshadow to allow access. I reported something very similar a couple of years ago on Fedora 14 https://bugzilla.redhat.com/show_bug.cgi?id=584161 -- Mark Orenstein

1 0

Heads up on major Firefox update incoming
by James Hogarth 23 Feb '12

23 Feb '12

As a heads up since this might have a large effect on people.... The upstream vendor has rebased form firefox 3.6 onto firefox 10... This effects both centos5 and centos6. I'm not sure reading this whether this is the extended update support version of if they intend to follow Mozilla's new release process....guess we'll find out when firefox 11 gets released... Here's the details: http://rhn.redhat.com/errata/RHEA-2012-0327.html Regards, James

1 0

Yum-cron with CentOS 5.7
by Sorin Srbu 23 Feb '12

23 Feb '12

Hi all, I use yum-cron with my new CentOS 6-installs and rather like it. So much in fact, that I tried getting it to work in the older CentOS 5-installs I also have scattered at the department. Unfortunately it doesn't seem to work for some reason. I found this; <<https://www.centos.org/modules/newbb/viewtopic.php?topic_id=22483>>, where it's suggested one use yum-updatesd instead. Is this still true? Should one avoid yum-cron if using CentOS 5? -- BW, Sorin ----------------------------------------------------------- # Sorin Srbu [Sysadmin, Systems Engineer] # Dept of Medicinal Chemistry, Phone: +46 (0)18-4714482 >3 signals> GSM # Div of Org Pharm Chem, Mobile: +46 (0)70-4250229 # Box 574, Uppsala University, Fax: +46 (0)18-4714482 # SE-751 23 Uppsala, Sweden Visit: BMC, Husargatan 3, D5:512b # Web: http://www.orgfarm.uu.se ----------------------------------------------------------- # () ASCII ribbon campaign - Against html E-mail # /\ # # This message was not sent from an iProduct! # # MotD follows: # CentOS: Tell it to your City Manager.

1 0

partitioning with fdisk
by James B. Byrne 22 Feb '12

22 Feb '12

CentOS-6.2 I created a new VirtIO disk for one of my virtual machines. Previous experience has taught me that I need to partition it before attempting to add the new storage to the physical volume set of the intended guest. Up to now I have simply accepted the defaults given by fdisk after telling it that I want a new partition. The defaults always exclude the first 2048 sectors. Disk /dev/vg_vhost01/lv_vm_inet09.harte-lyne.ca_01: 33.6 GB, 33554432000 bytes 109 heads, 61 sectors/track, 9856 cylinders, total 65536000 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x2b33a3c9 Device Boot Start End Blocks Id System /dev/vg_vhost01/lv_vm_inet09.harte-lyne.ca_01p1 2048 65535999 32766976 83 Linux Why? Is this space reserved for a boot partition? For my purposes can I simply use sector 0 to max sector size and override the default values provided by fdisk? -- *** 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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