Discuss January 2013

discuss@lists.centos.org

186 participants
157 discussions

SSD for Centos SWAP /tmp & /var/ partition
by Keith Roberts 03 Sep '25

03 Sep '25

Has anyone actually used a SSD in a Centos setup? My little experiment with a s/h WD drive for /tmp and SWAP partitions kicked the bucket on Wednesday, when the poor WD drive caught the click-of-death. It was a s/h drive to start with and lasted about 4 months. But that was without the /var/log/ partition being written to it, as I mounted that back onto /var/log from the original drive. So I had to install another (WD) drive, and repartion it and rebuild my RPM package database, from the backed-up Packages file. That seems to be all OK now. I'm wondering if it would be a good idea to use a new SSD for moving all the disk i/o to, that Linux likes to do so often. Plus putting SWAP onto a decent SSD should speed things up somewhat. Here's a short video of a laptop fitted with a SSD drive booting macOS, compared to a similar laptop booting from the standard HDD. The laptop with the SSD boots and loads some apps in 28 seconds. The other one takes twice as long. http://eshop.macsales.com/shop/SSD/OWC/Mercury_Extreme_Pro_6G/?utm_source=t… Kind Regards, Keith Roberts ----------------------------------------------------------------- Websites: http://www.karsites.net http://www.php-debuggers.net http://www.raised-from-the-dead.org.uk All email addresses are challenge-response protected with TMDA [http://tmda.net] -----------------------------------------------------------------

33 96

Create Virtual Machine via HTTP or FTP
by cbulist＠gmail.com 08 Jun '14

08 Jun '14

Hi, I'm trying to create a Virtual Machine using Network Install mode (I tried HTTP and FTP). The HTTP/FTP server where the installation files are located is the Host Machine. The URL that I'm using is: http://192.168.1.104/inst and the Automatic detect option detects the OS without problem. When the installation starts I got an error: Unable to retrieve http://192.168.1.104/inst/images/install.img I tried different path but I always get the same error. The host machine is a Centos 6.2 (2.6.32.-220.el6.x86_64) I really appreciate any help with this problem. Thanks in advance,

5 7

Building CentOS 6.2 custom install media
by Daniel Drake 14 Sep '13

14 Sep '13

Hi, For the OLPC school server ("XS") we are planning to move from our dated F9 setup to CentOS 6.2. Thanks for all the effort involved in producing this distro. One important part of this project is a 'respin' of the install media - we need to add a handful of packages from external repositories, and maybe run a command late in the install. Are the scripts/configurations used to produce the CentOS official CD/DVDs available? I guess this would be our most reliable/sensible starting point. I am familiar with pungi, kickstart, anaconda, etc, so just a simple git link would be enough to get me started. Thanks, Daniel

5 7

Re: [CentOS] sieveshell fails to start on CentOS 6.0
by Devin Reade 12 Jun '13

12 Jun '13

--On Wednesday, August 10, 2011 01:52:21 PM -0400 Harold Pritchett <harold(a)uga.edu> wrote: > [harold@newmick ~]$ sieveshell localhost > connecting to localhost > unable to connect to server at /usr/bin/sieveshell line 170. Try specifying both --user and --authname as appropriate. sieveshell can be misleading in its error messages, and you may actually have an authentication error rather than a connection error there. You could run it under strace to make sure. Devin

3 2

Virtual Machine Manager error
by Rajagopal Swaminathan 10 Apr '13

10 Apr '13

Greetings, I am getting the following error when I start the Virtual machine manager [root@centos Desktop]# uname -a Linux blah.blah.blah 2.6.32-220.2.1.el6.x86_64 #1 SMP Fri Dec 23 02:21:33 CST 2011 x86_64 x86_64 x86_64 GNU/Linux Error polling connection 'qemu:///system': internal error Cannot find suitable emulator for x86_64 Traceback (most recent call last): File "/usr/share/virt-manager/virtManager/engine.py", line 440, in _tick conn.tick() File "/usr/share/virt-manager/virtManager/connection.py", line 1414, in tick newNets, self.nets) = self._update_nets() File "/usr/share/virt-manager/virtManager/connection.py", line 1277, in _update_nets lookup_func, build_class) File "/usr/share/virt-manager/virtManager/connection.py", line 1209, in _poll_helper if not check_support(): File "/usr/share/virt-manager/virtManager/connection.py", line 501, in is_network_capable virtinst.support.SUPPORT_CONN_NETWORK) File "/usr/lib/python2.6/site-packages/virtinst/support.py", line 574, in check_conn_support return _check_support(conn, feature, conn) File "/usr/lib/python2.6/site-packages/virtinst/support.py", line 443, in _check_support actual_drv_ver = _hv_ver(conn, uri) File "/usr/lib/python2.6/site-packages/virtinst/support.py", line 376, in _hv_ver ret = cmd(*args) File "/usr/lib64/python2.6/site-packages/libvirt.py", line 2823, in getVersion if ret == -1: raise libvirtError ('virConnectGetVersion() failed', conn=self) libvirtError: internal error Cannot find suitable emulator for x86_64 any clues? TIA -- Regards, Rajagopal

12 17

CentOS 6 : Tip for significantly increasing battery life / reducing power consumption (Thinkpad X220 Tablet)
by Mathieu Baudier 24 Mar '13

24 Mar '13

Hello, I was not happy with the power consumption of CentOS 6 x86_64 on a new Lenovo Thinkpad x220 Tablet and I worked on reducing it. I just wanted to share with the list one of the changes which gave me the most significant improvement. As per http://www.williambrownstreet.net/blog/?p=387, add the following kernel arguments to the GRUB boot configuration: pcie_aspm=force i915.i915_enable_rc6=1 i915.lvds_downclock=1 i915.i915_enable_fbc=1 (in /boot/efi/EFI/redhat/grub.conf since I use EFI, /boot/grub/grub.conf otherwise) As measured using PowerTop, this made the power consumption decrease from 20W to 11W ! (I had already decreased it from 25W to 20W with the usual tips of disabling hardware, shutting down services, switching tuned profiles, etc.) All in all, battery time was more than multiplied by two, and the computer is now much more silent since the fan is not always running like mad in order to cool the processor. The bottom of the laptop is not anymore hot as hell. I don't know whether this would have an impact on other hardware, but it may be worth looking at it (even on servers?), since the above link points to descriptions of a regression in the kernel which seems more general. As a side note, the Power Management Guide of Red Hat is a good resource (analysis tools + tuned profiles): http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html-single/Po… Cheers, Mathieu PS: Do you think I should book a bug in the upstream bug tracker?

5 8

Advanced Persistent Threats; Why aren't we confining Firefox and Evolution?
by David McGuffey 21 Mar '13

21 Mar '13

Moat of the advanced persistent threats (APT) are initiated via e-mail. Opening an attachment or clicking on a web link starts the process. Why isn't Firefox and Evolution confined with SELinux policy in a way that APT can't damage the rest of the system? Why are we not sandboxing these two apps with SELinux? I've discovered some guidance for sandboxing Firefox using the 'sandbox' command. Once I test it a bit, I'll post the results back here. Seems to me that if this works, it should be the default. DaveM

4 7

evaluating backup systems: rsync
by ken 18 Mar '13

18 Mar '13

Considering using rsync on a couple systems for backup, I was wondering if it's possible, and if so how difficult is it, to delete files which have been backed up (in order to save space on the backup media). Anyone with experience doing this?

13 31

CentOS 6.3 - fail2ban not working properly + workaround
by SilverTip257 12 Mar '13

12 Mar '13

I recall others on this list are using fail2ban to block brute force login attempts. Packages are from the EPEL repo, so I'm just sharing some knowledge here. For about two months now I've had a CentOS 6.3 box (web host) in production that occasionally is ftp brute forced. Oddly enough fail2ban wasn't nabbing the perpetrators. I found that the iptables chain for VSFTP isn't created for one. I have finally come to find [0] that indicates there's a problem with the inotify backend. Setting backend=gamin in /etc/fail2ban/jail.conf gives me the iptables chain I expect to find and one blocked host. Hope this is helpful to somebody until a new version is commited to EPEL. <quote> yarikoptic: ok -- that point was not yet good ;) now (0.8.6-95-gc0c1232) that branch seems to work just perfect. If I hear no complaints or do not see problem with my instance -- I will merge it into master tomorrow, thus closing this issue </quote> [0] https://github.com/fail2ban/fail2ban/issues/44 ---~~.~~--- Mike // SilverTip257 //

3 5

CentOS 6 early panic on ESXi 4.1.0 build 800380
by Tilman Schmidt 12 Mar '13

12 Mar '13

I run VMware vSphere 4 Essentials with three almost identically configured ESXi 4.1 hosts and a mix of 32 and 64 bit guests including Windows 2003 and 2008 as well as CentOS 5 and 6. Recently I updated one of the hosts to build 800380. The new build runs Windows and CentOS 5 VMs fine, but CentOS 6 guests won't come up. I tried two different CentOS 6 VMs. Both have the latest standard kernel (2.6.32-279.5.2.el6.x86_64). Both run perfectly fine on one of the other VMware hosts still running ESXi 4.1.0 build 702113. On build 800380, both display the GRUB menu alright but freeze immediately afterwards, emitting the message PANIC: early exception 0d rip 10:ffffffff81038879 error 0 cr2 0 on the bottom of the virtual console. Both run perfectly fine again once I move them back to the host with the older ESXi build. From one of the failed boot attempts, I captured a VMware debug log which shows: Sep 11 17:21:19.628: vcpu-0| RDMSR: unknown MSR[0x1a0] (read as zero): rip=0xffffffff810388db count=1 Sep 11 17:21:19.628: vcpu-0| RDMSR: unknown MSR[0x1a0] (read as zero): rip=0xffffffff810388db count=2 Sep 11 17:21:19.629: vcpu-0| X86Fault_Warning: vmcore/vmm64/cpu/interp.c:427: cs:eip=0x10:0xffffffff81038879 fault=13 Sep 11 17:21:19.632: vcpu-0| Vix: [1125838 vmxCommands.c:9609]: VMAutomation_HandleCLIHLTEvent. Do nothing. Sep 11 17:21:19.632: vcpu-0| MsgHint: msg.monitorevent.halt (sent) Sep 11 17:21:19.632: vcpu-0| The CPU has been disabled by the guest operating system. Power off or reset the virtual machine. Ideas? aTdHvAaNnKcSe, Tilman

3 10

Jump to page:

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

Discuss January 2013