virt

virt@lists.centos.org

1610 discussions

Re: [CentOS-virt] LVM Lockout
by Christopher G. Stach II 15 Oct '09

15 Oct '09

----- "Ben M." <centos(a)rivint.com> wrote: > Gack. I added an additional Raid1 pair to my machine just before I > planned to bring it over to the office and I did something dumb and > locked out. > > I have the pv's, vg's and lv's cleared. All I need to do is get on > root > and remove a line from fstab, but I can't get it out of read only mode > > to save the edit. > > My root login at "Repair Filesystem" seems unable to make the file > writeable. I have done this in past with Knoppix, but can't seem to > file > the utility to make the write editable (same with CentOS and other > live > CD's, am downloading newer BackTrack now). The root filesystem's LV/device is not writable or your root filesystem is mounted read-only? If it's the latter, just ``mount -o remount,rw /''. -- Christopher G. Stach II

2 6

Re: [CentOS-virt] LVM Lockout
by Jorick Astrego 14 Oct '09

14 Oct '09

It's really simple: Boot Centos 5 CD Start rescue mode by typing # linux rescue # sudo -i # mkdir /mnt/root # mount -t ext3 /dev/whatever /mnt/root # nano /mnt/root/etc/fstab Regards, Netbulae Jorick Astrego Netbulae B.V. Janninksweg 127 7513 DH Enschede Tel. +31 (0)6 - 34 15 20 76 Fax. +31 (0)53 - 88 00 326 Email: jorick(a)netbulae.com Site: http://www.netbulae.com centos-virt-request(a)centos.org wrote: > Send CentOS-virt mailing list submissions to > centos-virt(a)centos.org > > To subscribe or unsubscribe via the World Wide Web, visit > http://lists.centos.org/mailman/listinfo/centos-virt > or, via email, send a message with subject or body 'help' to > centos-virt-request(a)centos.org > > You can reach the person managing the list at > centos-virt-owner(a)centos.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of CentOS-virt digest..." > > > Today's Topics: > > 1. LVM Lockout (Ben M.) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Wed, 14 Oct 2009 08:17:28 -0400 > From: "Ben M." <centos(a)rivint.com> > Subject: [CentOS-virt] LVM Lockout > To: Discussion about the virtualization on CentOS > <centos-virt(a)centos.org> > Message-ID: <4AD5C158.9080207(a)rivint.com> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Gack. I added an additional Raid1 pair to my machine just before I > planned to bring it over to the office and I did something dumb and > locked out. > > I have the pv's, vg's and lv's cleared. All I need to do is get on root > and remove a line from fstab, but I can't get it out of read only mode > to save the edit. > > My root login at "Repair Filesystem" seems unable to make the file > writeable. I have done this in past with Knoppix, but can't seem to file > the utility to make the write editable (same with CentOS and other live > CD's, am downloading newer BackTrack now). > > > > > > > ------------------------------ > > _______________________________________________ > CentOS-virt mailing list > CentOS-virt(a)centos.org > http://lists.centos.org/mailman/listinfo/centos-virt > > > End of CentOS-virt Digest, Vol 26, Issue 11 > ******************************************* >

2 1

Xen to KVM migration
by Dennis J. 14 Oct '09

14 Oct '09

Hi, I'm thinking about how to go about migrating our Xen VMs to KVM. Migrating the configuraton should be easy using the virsh dumpxml/define commands but what is the best way to transfer the (logical volume based) images without too much downtime for the guest system? Can rsync operate on logical volumes? If so I could potentially use "dd" to transfer an initial copy of the image to the destination host and then shut down the guest, rsync the logical volumes which shouldn't take too long as not much data has to be transfered thanks to the initial "dd" and then boot the guest on the new machine. Is something like this possible or would you do something different? Regards, Dennis

3 4

domU shutdown with cx88 crashes dom0
by Christian Schuermann 10 Oct '09

10 Oct '09

Hi, I've got a big problem with a cx88 DVB card. It is passed through to a CentOS 5.3 domU (dom0 is CentOS 5.3 as well), but when I shutdown the domU, this happens: cx88[0]: mpeg risc op code error cx88[0]: mpeg - dma channel status dump cx88[0]: cmds: initial risc: 0xffffffff cx88[0]: cmds: cdt base : 0xffffffff cx88[0]: cmds: cdt size : 0xffffffff cx88[0]: cmds: iq base : 0xffffffff cx88[0]: cmds: iq size : 0xffffffff cx88[0]: cmds: risc pc : 0xffffffff cx88[0]: cmds: iq wr ptr : 0xffffffff cx88[0]: cmds: iq rd ptr : 0xffffffff cx88[0]: cmds: cdt current : 0xffffffff cx88[0]: cmds: pci target : 0xffffffff cx88[0]: cmds: line / byte : 0xffffffff cx88[0]: risc0: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: risc1: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: risc2: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: risc3: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq 0: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq 1: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq 2: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq 3: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq 4: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq 5: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq 6: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq 7: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq 8: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq 9: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq a: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq b: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq c: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq d: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq e: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: iq f: 0xffffffff [ INVALID sol eol irq2 irq1 23 22 21 20 19 18 cnt1 cnt0 resync 14 13 12 count=4095 ] cx88[0]: fifo: 0x00186400 -> 0x187400 cx88[0]: ctrl: 0x001807c0 -> 0x180820 cx88[0]: ptr1_reg: 0xffffffff cx88[0]: ptr2_reg: 0xffffffff cx88[0]: cnt1_reg: 0xffffffff cx88[0]: cnt2_reg: 0xffffffff This loops forever eating every available cpu cycle. The dom0 becomes unusably slow until I manually destroy the domU. The domU runs 2.6.18-128.1.10.el5xen with video4linux-kmdl-2.6.18-128.1.10.el5xen-20090415-88.0.4.el5 (there are no video4linux-kmdls for the latest kernel yet). Manually unloading the modules before shutting down has no effect. Without video4linux-kmdl installed, everything works fine. I hope you can help me. Regards, Chris

1 2

Centos virsh - add a physical device
by For＠ll 30 Sep '09

30 Sep '09

Hi, If I create a guest which uses (hvm) can I add access to physical device like cdrom? Regards, For@ll

5 10

Resizing disks for VMs
by Dennis J. 28 Sep '09

28 Sep '09

Hi, Is there a way to make a PV xen guest aware of a size change of the host disk? In my case I'm talking about a Centos 5.3 host using logical volumes as storage for the guests and the guests running Centos 5.3 and LVM too. What I'm trying to accomplish is to resize the logical volume for the guest by adding a few gigs and then make the guest see this change without requiring a reboot. Is this possible maybe using some kind of bus rescan in the guest? Regards, Dennis

5 7

IP aliases of CentOS Guests not accessible running 2.6.18-164.el5xen
by Devraj Mukherjee 28 Sep '09

28 Sep '09

Hi all, First of all I am posting this on two lists for a reason, because the issue being reported by me could be because of a change delivered by a Kernel update or due to Xen. I have recently managed to update all Xen Guest domains running CentOS 5.3 to the latest bunch of updates + Kernel. My Xen host also runs the same CentOS 5.3 updated to all recent packages. The Guest images in concern had IP aliases assigned to them. Everything worked until I ran the updates and restarted. Since I have restarted the aliased IP addresses are no longer accessible from the outside world, they can still be accessed from all machines (guest virtual machines) in the subnet (ping, services like http). I have removed all firewall rules to test if that would have effected it without any change (any the fact that I can access them within the subnet proves its not the firewall). Is there anything special I have to do to enable aliasing? May be this is a Xen issue? I am suspecting the Xen host, but not sure how to go about proving this. Any information would be greatly appreciated. My Guests do run fail2ban (delivered via atrpms) and iptables (allowing only HTTP, HTTPS and SSH) connections. PS for obvious reasons I am not posting IP addresses and routes etc first up, I can make that information available if required. -- "The secret impresses no-one, the trick you use it for is everything" - Alfred Borden (The Prestiege)

2 1

Re: [CentOS-virt] Domain0 with Kernel 2.6.18-92.1.22.el5xen fails to boot Guests with Kernel 2.6.18-164.el5xen
by Christopher G. Stach II 27 Sep '09

27 Sep '09

----- "Devraj Mukherjee" <devraj(a)gmail.com> wrote: > Hi all, > > I am in a bit of a fix here, I have several Guests paravirtualized > running on a Dom0 that is currently running the 2.6.18-92.1.22.el5xen > Kernel. All my guests (administered by different people) have > subsequently been updated to later versions of the kernel (namely > 2.6.18-164.el5xen or 2.6.18-128.4.1.el5xen). [...] > I restarted a Guest that's now trying to boot with the > 2.6.18-164.el5xen Kernel and it spits out messages like > XENBUS: Waiting for devices to initialise: 295s...290s... > > and eventually reboots. IIRC, there were changes to the block back-/frontend drivers a while back, but that probably wouldn't do this. I would first look to make sure that your dom0 Xen daemons are in good condition. Occasionally, they will die or stop working. Watching the logs when you start your guest may give you some clues as to what dom0 may be hanging on. Restarting xend and/or xenconsoled (typically when your guest can't get a console or when ``xm console'' mysteriously doesn't work) may help. Anyway, you should update your dom0 kernel. That's pretty old. :) -- Christopher G. Stach II

1 0

xen & iSCSI
by Daniel De Marco 24 Sep '09

24 Sep '09

Hi, I'm setting up xen (on centos 5.3) and I'm facing a weird performance issue with iSCSI. I attach the iSCSI targets to dom0 and if I use them from dom0 I obtain good performance with simple dd tests (~100MB/s both reading and writing). I then use the block devices for the domU and if I repeat the same dd test from within the domU the write performace is still good (~100MB/s), but the read performance is cut in half (~55MB/s). I tried changing several parameters like read_ahead and such, but I can not obtain a good read performance in the domU. Any idea? Thanks, Daniel.

2 5

Writing iptables for inbound connections with libvirt
by carlopmart 16 Sep '09

16 Sep '09

Hi all, I have installed a CentOS 5.3 x86_64 server with kvm and libvirt to do some tests for future virtualized deployments. My environment: eth0 --> 172.25.50.1/24 ("public" host ip) virbr0 ---> 192.168.122.1/24 (natted interface installed by libvirt) virbr1 ---> 172.26.50.0/24 (internal virtualized network, whithout physical interface binded) Between 192.168.122.0/24 network and 172.26.50.0/24 network I have installed a virtual firewall. So to reach 172.26.50.0/24 network, all connections needs to come from 192.168.122.0/24 network. I need to insert some iptables rules to allow access to some services installed on 172.26.50.0/24 network like smtp,http,ftp, etc. How can I configure libvirt to forward and nat these services coming from 172.25.50.0/24 network to a specific IP under 192.168.122.0/24 network?? Or do I need to use /etc/sysconfig/iptables configuration?? Some examples, please??. Many thanks. -- CL Martinez carlopmart {at} gmail {d0t} com

1 0

Jump to page:

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

virt