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 the non-global zone (in our case zone01). # zlogin zone01 shutdown 2. Set the hostid of your choice using zonecfg command. # zonecfg -z zone01 zonecfg:zone01> set hostid=80f0c086 … [Read more...] about How to provide unique hostid for a non global zone
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 - Speeds up booting by loading services concurrently. - Allows you to manage various types of units on a system, example: services (name.service) targets (name.target) devices … [Read more...] about CentOS / RHEL 7 : Beginners guide to systemd
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 behaviour is controlled via the dumpadm "Dump Content" setting via the "-c" command line parameter. The kernel's memory consumption will vary from system to system, so it is not possible to give a … [Read more...] about How To Determine Approximate Solaris Crash Dump File Size Requirements
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 with only the services that are required for a specific purpose. To list the predefined systemd run level target units : # find / -name … [Read more...] about CentOS / RHEL 7 : How to set default target (default runlevel)
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 forever This … [Read more...] about CentOS / RHEL 7 : How to modify Network Interface names
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 and similar to run levels, target units allow you to start a system with only the services that are required for a specific purpose. RHEL 7 is distributed with a set … [Read more...] about CentOS / RHEL 7 : Beginners guide to systemd targets (replacement of SysV init run levels)
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 Solaris 10 update 9, two files are created, the unix.X and the vmcore.X. Note: Right after the reboot caused by a system panic the savecore command is … [Read more...] about Solaris : How to validate that the crash dump was created properly
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 haltHalts the system poweroff systemctl poweroffPowers off the system reboot systemctl rebootRestarts the system pm-suspend systemctl suspendSuspends the … [Read more...] about CentOS / RHEL 7 : Shutting Down, Suspending, or Rebooting Commands (systemctl)
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 want guest domains to communicate with the outside world then one should directly plumb up the switch vsw's along with the primary domain's network interface used to create those vsws (In our … [Read more...] about LDOMs troubleshooting : guest and control domains can not talk to each other but can talk with anyone else on the network
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 crash dump in case of a LDOM. From Control domain A panic signal can be sent to guest ldom (e.g. ldom01) from the control domain. control-domain # ldm panic/panic-domain ldom01 From … [Read more...] about How to Collect a Forced Crash Dump of a Hanging Solaris Guest LDom