Re: [CentOS-virt] Getting guest to detect new drive without reboot
Partprobe Sent from my iPad On Sep 19, 2011, at 21:51, Emmanuel Noobadmin centos.ad...@gmail.com wrote: I've got a CentOS 5.6 guest running on 6.0 host. Using virsh attach-disk, I attached a new raw file as vdc However, the guest does not detect this new disk. In the past, I've used the following echo 0 0 0 /sys/class/scsi_host/host#/scan command to make a CentOS system scan for new drives. However in the guest, there is no host in scsi_host so this isn't an option. I can't seem to find any information on doing this any other way apart from a reboot. Does anybody know if there is any other way? ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Getting guest to detect new drive without reboot
On 9/20/11, Ian Forde ianfo...@gmail.com wrote: Partprobe Thanks for pointing this out, although due to time pressure I did the nasty in the end, kicked everybody off and rebooted the server. But I'll keep this in mind the next time I need to do this again, probably sooner than later. ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
[CentOS-virt] Network traffic control/shaping of guest interfaces
I've been using tc/htb for network control previously to control bandwidth available to different services running on their own IPs on a unvirtualized host. Now, I have put them into their own guest VM. I would like to be able to do something similar to ensure the more crucial service gets more bandwidth as well as ensuring ssh always get reserved bandwidth. However, when I try the good old tc/htb commands on the host, it fails to do anything useful. My script that works on the non-virtualized setup was this TCADD=tc class add dev eth0 parent $TCADD 1:0 classid 1:1 htb rate 1250kbps ceil 1250kbps $TCADD 1:1 classid 1:10 htb rate 25kbps ceil 150kbps prio 0 $TCADD 1:1 classid 1:11 htb rate 100kbps ceil 300kbps prio 1 $TCADD 1:1 classid 1:12 htb rate 300kbps ceil 600kbps prio 1 $TCADD 1:1 classid 1:19 htb rate 75kbps ceil 150kbps prio 2 TFADD=tc filter add dev eth0 protocol ip parent $TFADD 1:0 prio 0 u32 match ip dport 10022 0x flowid 1:10 $TFADD 1:0 prio 1 u32 match ip dst public ip ipaddress 1 flowid 1:11 $TFADD 1:0 prio 1 u32 match ip dst public ip address 2 flowid 1:12 I can't put the restrictions within the guest because I don't want the individual VM admins to be able to stop the script from running. On my new host, I have bridged networking with br0, eth0 and guests running off vnetn. I've tried applying tc on br0, eth0, vnetn but they don't seem to have any effect based on a 20MB FTP test. I've been googling for a while to find an solution but haven't hit on anything apart from using yet another firewall/router sitting between everything and the Internet. Is there any other solution apart from that? ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Network traffic control/shaping of guest interfaces
On 09/20/2011 08:20 PM, Emmanuel Noobadmin wrote: I can't put the restrictions within the guest because I don't want the individual VM admins to be able to stop the script from running. On my new host, I have bridged networking with br0, eth0 and guests running off vnetn. I've tried applying tc on br0, eth0, vnetn but they don't seem to have any effect based on a 20MB FTP test. I've been googling for a while to find an solution but haven't hit on anything apart from using yet another firewall/router sitting between everything and the Internet. Is there any other solution apart from that? I would convert bridged setup on host to the routed one. Then you will have several separate interfaces on host, each one used for communication with only one guest and it will be easy to attach tc to them. Regards, Nenad ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Network traffic control/shaping of guest interfaces
On 9/21/11, Nenad Opsenica ne...@panline.net wrote: I would convert bridged setup on host to the routed one. Then you will have several separate interfaces on host, each one used for communication with only one guest and it will be easy to attach tc to them. In other words, there's no solution for bridged networking? How would routed networking impact the guest performance? The reason I went for bridged was that it was supposed to have the least overheads and here http://www.cyberciti.biz/faq/rhel-linux-kvm-virtualization-bridged-networking-with-libvirt/ said it was required for servers with multiple network cards. Which is the case here because I have 3 NICs, one each for Internet traffic, networked storage and user access. Although, admittedly on hindsight, given the number of users in the company, it probably isn't going to be noticeable I would still like to know what kind of impact would it cause. That is assuming routed networking can work on the server given the NICs in it. ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Network traffic control/shaping of guest interfaces
On 09/20/2011 08:44 PM, Emmanuel Noobadmin wrote: On 9/21/11, Nenad Opsenicane...@panline.net wrote: I would convert bridged setup on host to the routed one. Then you will have several separate interfaces on host, each one used for communication with only one guest and it will be easy to attach tc to them. In other words, there's no solution for bridged networking? I'm afraid so. Maybe it could be possible in some strange setup, but I think it would be too complicated, if possible at all. How would routed networking impact the guest performance? The reason I went for bridged was that it was supposed to have the least overheads and here http://www.cyberciti.biz/faq/rhel-linux-kvm-virtualization-bridged-networking-with-libvirt/ said it was required for servers with multiple network cards. Which is the case here because I have 3 NICs, one each for Internet traffic, networked storage and user access. You can combine bridged and routed setup - for example, use bridging for storage, routing for internet and user access. Using routed setup have one more advantage - you can use firewall on host to filter guests' traffic. ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] Network traffic control/shaping of guest interfaces
On 9/21/11, Nenad Opsenica ne...@panline.net wrote: You can combine bridged and routed setup - for example, use bridging for storage, routing for internet and user access. Using routed setup have one more advantage - you can use firewall on host to filter guests' traffic. Thanks for the tip, I'll have to look into this during the weekends when, almost guaranteed by virtue of noobness, I will probably kill connectivity to the services for hours and render it useless for work :D ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
Re: [CentOS-virt] KVM CO 5.6 VM guest crashes running iSCSI
It was resolved by re-installing the KVM host with CentOS 6.0, unfortunately there is not official CentOS 5.6 - CentOS 6.0 upgrade path. Vladimir On Wed, Sep 14, 2011 at 3:56 PM, Momonth momo...@gmail.com wrote: Hi All, I'm running KVM host on CentOS 5.6 x64, all of my guests are CO 5.6 x64 as well. I create / run VMs via libvirt. Here are the packages I have: # rpm -qa | egrep kvm|virt kvm-83-224.el5.centos python-virtinst-0.400.3-11.el5 kvm-qemu-img-83-224.el5.centos kmod-kvm-83-224.el5.centos libvirt-python-0.8.2-15.el5 etherboot-zroms-kvm-5.4.4-13.el5.centos libvirt-0.8.2-15.el5 libvirt-devel-0.8.2-15.el5 The problem: I attached an iSCSI LUN (netapp appliance) to a guest and everything work fine with iscsi-initiator-utils-6.2.0.872-6.el5: LUN discovery, attaching to the host etc. After that I'm trying to copy ~ 140Gb of data to that LUN via scp from another server in the network and the VM crashes after ~ 1 hour of copying .. Nothing in the VM / KVM host logs importunately. Who has / had similar issues with iSCSI LUNs being connected to a guest? Thanks, Vladimir ___ CentOS-virt mailing list CentOS-virt@centos.org http://lists.centos.org/mailman/listinfo/centos-virt
