Question : How to set a unique hostid for non-global zone ? Answer: Per default, a non global zone in Solaris gets the same hostid as global zone. Starting from Solaris 10 update 9, It is allowed to set unique hostid for a non-global zone using zonecfg command. Procedure to set unique hostid 1. Shtidown […]
Archives for March 2016
CentOS / RHEL 7 : Beginners guide to systemd
systemd is the new system and service manager in RHEL 7. It is backward compatible with SysV init scripts used by previous versions of Oracle Linux including RHEL 6. systemd is the first process that starts after the system boots, and is the final process that is running when the system shuts down. Features – […]
How To Determine Approximate Solaris Crash Dump File Size Requirements
The amount of disk space required by Solaris in order to capture a crash dump will depend upon a number of factors. By default, Solaris will capture just the kernel’s memory pages. But it is also possible to capture user pages which would, in most cases, result in a much larger crash dump file. This […]
CentOS / RHEL 7 : How to set default target (default runlevel)
Within Oracle Linux 7 introduction of systemd (systemd uses ‘targets’).The file /etc/inittab is no longer used to set the default run level. Editing /etc/inittab file with the same manner under Oracle Linux 5/6 will have no effect in Oracle Linux 7. Target units have a .target extension. Target units allow you to start a system […]
CentOS / RHEL 7 : How to modify Network Interface names
On CentOS / RHEL 7, a new naming scheme is introduced. For instance: # ip addr show ….. eno1: [BROADCAST,MULTICAST,UP,LOWER_UP] mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 6c:0b:84:6c:48:1c brd ff:ff:ff:ff:ff:ff inet 10.10.10.11/24 brd 10.10.10.255 scope global eno1 inet6 2606:b400:c00:48:6e0b:84ff:fe6c:481c/128 scope global dynamic valid_lft 2326384sec preferred_lft 339184sec inet6 fe80::6e0b:84ff:fe6c:481c/64 scope link valid_lft forever preferred_lft […]
CentOS / RHEL 7 : Beginners guide to systemd targets (replacement of SysV init run levels)
Previous versions of CentOS/RHEL Linux use SysV init run levels. These run levels provided the ability to use systems for different purposes and only start the services needed for a specific purpose, at a specific run level. In RHEL 7, run levels have been replaced with systemd target units. Target units have a .target extension […]
Solaris : How to validate that the crash dump was created properly
After a panic, the crash dump is stored under the directory defined as “Savecore directory” on the dumpadm output. The default is /var/crash/`uname -n`. Starting with Solaris 10 Update 9, the crash dump is stored in a single file called vmdump.X, where X is a consecutive number as defined in the /var/crash/`uname -n`/bounds file. Before […]
CentOS / RHEL 7 : Shutting Down, Suspending, or Rebooting Commands (systemctl)
In CentOS/RHEL 7, the systemctl utility replaces some older power management commands used in previous versions. The table below compares the older and new equivalent systemctl commands. The old commands listed in the table still exist for compatibility reasons. Older Command systemctl equivalent Description halt systemctl halt Halts the system poweroff systemctl poweroff Powers off […]
LDOMs troubleshooting : guest and control domains can not talk to each other but can talk with anyone else on the network
One of the common mistakes done while configuring the guest LDOMs for the first time is – to not configure control domain for inter domain communications. In this case the control domain and guest ldoms can talk to everyone on the network but not to each other. There are 2 scenarios: 1. If one just […]
How to Collect a Forced Crash Dump of a Hanging Solaris Guest LDom
A Solaris system panics when it encounters an unrecoverable software or hardware error. When a panic occurs, it saves data about the state of the system and then reboots. A crash dump is created so that an Oracle engineer can determine the reason for the panic. The post describes a manual way to generate a […]