Category: Technology

Install ktap on RHEL

My RHEL is 7.0, the minimal installation. Build ktap, it outputs the following error:

[root@redhat ktap-master]# make
    CHK libelf
Makefile:108: No libelf found, disables symbol resolving, please install elfutils-libelf-devel/libelf-dev
make -C /lib/modules/3.10.0-123.el7.x86_64/build M=/root/ktap-master modules
make: *** /lib/modules/3.10.0-123.el7.x86_64/build: No such file or directory.  Stop.
make: *** [mod] Error 2

(1)

To fix “No libelf found, disables ...” error, you need to install elfutils-libelf-devel package:

[root@redhat ktap-master]# yum install elfutils-libelf-devel
Loaded plugins: product-id, subscription-manager
This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register.
Resolving Dependencies
--> Running transaction check
---> Package elfutils-libelf-devel.x86_64 0:0.158-3.el7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved
......

(2)

To fix “*** /lib/modules/3.10.0-123.el7.x86_64/build: No such file or directory.” error, you need to install kernel-devel package:

[root@redhat ktap-master]# yum install kernel-devel
Loaded plugins: product-id, subscription-manager
This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register.
Resolving Dependencies
--> Running transaction check
---> Package kernel-devel.x86_64 0:3.10.0-123.el7 will be installed
--> Finished Dependency Resolution

Dependencies Resolved

Then make is OK!

 

How to install git on SUSE

On SUSE, when you want to install git, execute “zypper in git“:

nanxiao:~ # zypper in git
Loading repository data...
Reading installed packages...
'git' not found in package names. Trying capabilities.
No provider of 'git' found.
Resolving package dependencies...

Nothing to do.

You should use “zypper in git-core“:

nanxiao:~ # zypper in git-core
Loading repository data...
Reading installed packages...
Resolving package dependencies...

The following 2 NEW packages are going to be installed:
  git-core perl-Error

2 new packages to install.
Overall download size: 3.2 MiB. Already cached: 0 B. After the operation, additional 19.5 MiB will be used.
......

Enjoy git now:

nanxiao:~ # git
usage: git [--version] [--help] [-C <path>] [-c name=value]
           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]
           [-p|--paginate|--no-pager] [--no-replace-objects] [--bare]
           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]
           <command> [<args>]

The most commonly used git commands are:
......

 

Select disk when installing SLES 12

When installing SLES(SUSE Linux Enterprise Server) 12, I find the installation may corrupt other OSs. For example, I have two disks: the first(/dev/sda) has been installed the Fedora, and I want to install SLES on disk 2(/dev/sdb) :

2

 

If no attention, the SLES may occupy both disks:

5

The solutions is select “Create Partition Setup...“: 6

Select the second disk:

3

Then “Next“, “Next“…. The SLES can do the partition automatically:

4

You can install SLES now.

 

Why does qemu complain “No IOMMU found. Unable to assign device”?

When follow How to assign devices with VT-d in KVM tutorial in KVM site, you may encounter qemu-system-x86_64complains:

......No IOMMU found.  Unable to assign device......

The root cause is the KVM_DEVICE_ASSIGNMENT configuration option is deprecated, and the code in kernel KVM part is like this:

#ifdef CONFIG_KVM_DEVICE_ASSIGNMENT
    case KVM_CAP_IOMMU:
        r = iommu_present(&pci_bus_type);
        break;
#endif

So you should use VFIO feature instead.

If you still to want to use KVM_DEVICE_ASSIGNMENT feature, please rebuild the kernel with KVM_DEVICE_ASSIGNMENT option on.

Reference:
A question about “CONFIGKVMDEVICE_ASSIGNMENT” configuration