We set up Xen F19 VMs on a Xen 3.4.3 / 2.6.32.13 xenified kernel. Check here.). However, we find the Xen VM keeps reporting: kernel netfront: Too many frags and skb rides the rocket in the dmsg. This solves the problem (assume in physical server vif1.0 is for the eth0 on the VM): On the
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Tag: VM
How to install IE under wine on Linux?
Posted onHow to install IE under wine on Linux? Just need it for some testing. Do not want to reboot to Windows. We ever had ies4linux. But it is obsoleted now. linie is the latest effort. But there are issues and you may need to fix some problems by yourself. Installing a Windows VM may be
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How to set up the Java environment in Linux?
Posted onI am using Fedora 20. I installed the rpm from Oracle for the Oracle JDK. How to set up the environment so that the Java environment is Oracle JDK instead of the OpenJDK? The Oracle JDK is install to /usr/java/ directory. On my Fedora 20, it looks like this: $ ls /usr/java -l total 4
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How to use LVM groups with libvirt
Posted onlibvirt uses files for VM images by default under /var/lib/libvirt/images/. LVM is a convenient tool for managing VM images. How to use LVM groups with libvirt? This post discusses the method to add LVM groups as a storage pool for libvirt: http://ailoo.net/2011/02/use-a-lvm-volume-group-with-libvirt/ For a general introduction of the storage management in libvirt, please check: http://libvirt.org/storage.html
Xen HVM DomU configuration file
Posted onAn example of Xen HVM DomU configuration file. An example for install the OS from an ISO: name=”10.0.1.235″ vcpus=2 memory=2048 shadow_memory=8 disk=[‘file:/lhome/xen/vm-10.0.1.235/vmdisk0,xvda,w’, ‘file:/lhome/Linux-x86_64-DVD.iso,xvdc:cdrom,r’] vif=[‘bridge=xenbr0′] kernel=’/usr/lib/xen/boot/hvmloader’ builder=’hvm’ device_model=’/usr/lib64/xen/bin/qemu-dm’ extra=” vnc=1 vnclisten=”0.0.0.0″ vncpasswd=’1234567′ # vncdisplay=1 vncconsole=1 on_reboot=’restart’ on_crash=’restart’ An example for run the VM after installation: name=”10.0.1.235″ vcpus=2 memory=2048 shadow_memory=8 disk=[‘file:/lhome/xen/vm-10.0.1.235/vmdisk0,xvda,w’] vif=[‘bridge=xenbr0′] kernel=’/usr/lib/xen/boot/hvmloader’ builder=’hvm’ device_model=’/usr/lib64/xen/bin/qemu-dm’ extra=” vnc=1
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Quick method to sniff the data left on a Linux VM in the public cloud
Posted onVM disks in public cloud may be shared by customers. This is privacy problem. Is there a quick method to sniff the data left on a Linux VM? One possible method: # dd if=/dev/xvda bs=1M | strings -n 100 > strings.txt Using the dd and strings which are pervasive on Linux systems.
How to attach and mount Xen DomU’s disk to Dom0
Posted onHow to attach and mount Xen DomU’s disk to Dom0 To attach phy:vg_xen/vm-10.1.1.228 to xvda on Domain-0: # xm block-attach Domain-0 phy:vg_xen/vm-10.1.1.228 xvda w Mount the new partition /dev/xvda2 to /mnt/xvda2: # mount /dev/xvda2 /mnt/xvda2 After finishing using the partition, umount it and detach it: # umount /mnt/xvda2/ # xm block-detach Domain-0 xvda
Windows 7 64-bit fails to install on VirtualBox / Linux with status code 0xc0000225
Posted onWindows 7 64-bit fails to install on VirtualBox on Linux with status code 0xc0000225: “Windows failed to start. A recent hardware or software change might be the cause. To fix the problem: 1. insert your Windows installation disc and restart your computer. 2. Choose your language settings, and click “Next.” 3. Click “Repair your Computer”.
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Xen: Passing kernel parameters to DomUs
Posted onHow to pass kernel parameters to Xen DomUs ? Kernel paremeter may be needed to be passed to a Xen DomU. For example, when the DomU fails to boot and we want to check it in ‘single’ mode. We can simply start the DomU with the “extra=” syntax. For example, to add ‘single’ to the
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How to Install Paravirtualized CentOS 7 DomU on Xen
Posted onThis post introduces how to install a paravirtualized CentOS 7 DomU on Xen. The very common way of installing DomU does not work for CentOS 7. A little trick to set the repository and the network used by the VM should be used by adding a setting strings to the “extra=” field for this VM.
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x-data-plane feature in QEMU/KVM
Posted onAbstract In systems, sometimes, we use one global lock to keep synchronization among different threads. This principle also happens in QEMU/KVM (http://wiki.qemu.org/Main_Page) system. However, this may cause lock contention problem. The performance/scalability of whole system will be decreased. In order to solve this problem in QEMU/KVM, x-data-plane feature is designed/implemented, which the high-level idea is
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How to Create Fedora 20 Domain-U on Fedora 20 Domain-0
Posted onIn this post, creating a file-backed virtual block device (VBD) and installing Fedora 20 in the Xen DomU via internet will be introduced. This domain is created on a Fedora 20 Dom0 as introduced in https://www.systutorials.com/installing-xen-on-fedora-20-as-domain-0/. For better performance, you may consider using LVM backed VM. Create file-backed VBD The actual space of VBD will
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Installing Xen on Fedora 20 as Domain-0
Posted onI ever introduced [[installing-xen-domain-0-on-fedora-17]] as the first try to use the xen package delivered from Fedora and get away from manually compiling Xen and patching the kernel. In this post, I introduce installing Xen Dom0 on Fedora 20. Installing Xen First, install the xen pacakges: # yum install xen The Linux kernel is already ready
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Directly SSH to Hosts’ Internal IPs Through the Gateway
Posted onWe have many hosts with internal/LAN IPs like 10.0.3.* behind a gateway and the hosts with LAN IPs can connect to the Internet through the gateway. We used iptables to forward port from the gateway to internal IPs so that users from hosts with Internet connections can SSH to the gateway’s forwarded port to log
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Java Calling Native Functions in .DLL on Windows
Posted onHow to call a function in .dll from Java on Windows is introduced in this post with an example. Platforms used: OS: Microsoft Windows XP [5.1.2600] C to .dll compiler: MS Visual Studio 2008 JDK: java -version java version “1.6.0_05” Java(TM) SE Runtime Environment (build 1.6.0_05-b13) Java HotSpot(TM) Client VM (build 10.0-b19, mixed mode, sharing)
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Script: Shutting Down All Xen VMs on a Server
Posted onShutting down servers is a common operations for managing a cluster. However, if this server is configured to a Xen Dom0 and has Xen VMs (DomUs), the VMs should be shutdown first to avoid data lost on these VMs. xm supports a -a option to shutdown all VMs: # xm shutdown -a Add the -w
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Installing Fedora 17 PV Domain-U on Xen with PXE Booting
Posted onAn introduction to the general method of installing Domain-U on Xen is introduced here: Setting Up Stable Xen DomU with Fedora: Unmodified Fedora 12 on top of Xenified Fedora 12 Dom0 with Xen (this is a general introduction, some details are changed, such as ‘xl’ replacing ‘xm’, LVM backing the disk for higher performance. But
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How to Install Xen on Fedora as Domain-0 (Fedora 17)
Posted onThe new development of Xen and Linux kernel make it easy to install Xen on Fedora as the Domain-0 now. This post uses Fedora 17 as an example platform to introduce how to set up Domain-0 on Fedora Linux. Compared to our old method (https://www.systutorials.com/setting-up-stable-xen-dom0-with-fedora-xen-3-4-3-with-xenified-linux-kernel-2-6-32-13-in-fedora-12/) which requires manually compiled Xen and patched kernel, the current
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How to Flush Linux File System Caches
Posted onWe may drop the file system caches on Linux to free up memory for applications. Kernels 2.6.16 and newer provide a mechanism via the /proc/ to make the kernel drop the page cache and/or inode and dentry caches on command. We can use this mechanism to free up the memory. However, this is a non-destructive
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Setting Up Ubuntu DomU on Xen: Ubuntu 10.10 on Fedora Xen Dom0
Posted onSetting up Ubuntu 10.10 DomU on top of Fedora Xen Dom0 is introduced in this post. The process of setting up Ubuntu 10.10 DomU is the same as Setting Up Stable Xen DomU with Fedora: Unmodified Fedora 12 on top of Xenified Fedora 12 Dom0 with Xen 4.0 This post only show the difference which
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