Unix Administration

ZFS manages its cache differently to other filesystems such as: UFS and VxFS.  ZFS' use of kernel memory as a cache results in higher kernel memory allocation as compared to UFS and VxFS filesystems.  Monitoring a system with tools such as vmstat would report less free memory with ZFS and may lead to unnecessary support calls. SOLUTION This is due to ZFS's cache management being different from UFS and VxFS filesystems.  ZFS does not use the page cache, unlike other filesystems such as UFS and VxFS.  ZFS's caching is drastically different from these old filesystems where cached pages can be moved to the cache list after being written to the backing store and thus counted as free memory. ZFS affects the VM subsystem in terms of memory management.  Monitoring of systems with vmstat(1M) and prstat(1M) would report less free memory when ZFS is used heavily ie, copying large file(s) into a ZFS filesystem.  The same load running on a UFS filesystem would u...

On : 10 8/11 U10 version, Ops Center Problem with Live Migration of LDOM under OpsCenter 12C U1 During the Live Migration of the LDOMs under OpsCenter, it creates an user on the target server "xvmCxxxx" and set a random password. Error message is generated when this user account is created and password is assigned, why ?. The policy of password creation for our Server is as follows: MAXWEEKS=12 MINWEEKS=1 PASSLENGTH=6 WARNWEEKS=2 DICTIONLIST=/usr/share/lib/dict/words MINUPPER=1 MINLOWER=1 MINDIGIT=1 MINSPECIAL=1 NAMECHECK=YES HISTORY=10 SOLUTION There is a CR, which is listed as fixed in the 12c initial release. The fix added a value to the  XVM.properties  file located in the  /opt/sun/n1gc/lib/  directory. Lines 49-53 describe the random-string-prefix value that is defaulting to "two letters and a digit" for the random generated password. From CR engineer: We compute randomly a password for a temporary account that will last for the time of the migration...

Sun Logical Domains or LDoms is a full virtual machine that runs an independent operating system instance and contains virtualized CPU, memory, storage, console, and cryptographic devices. This technology allows you to allocate a system resources into logical groupings and create multiple, discrete systems, each with their own operating system, resources, and identity within a single computer system. We can run a variety of applications software in different logical domains and keep them independent of performance and security purposes. A zone is a virtual operating system abstraction that provides a protected environment in which applications run. The applications are protected from each other to provide software fault isolation. To ease the labor of managing multiple applications and their environments, they co-exist within one operating system instance, and are usually managed as one entity. LDOMs allow you to assign your hardware to different virtual hosts for ...

  Virtualization - Using logical domains (LDom) You have heard about this word  "virtualization" now days in the  IT world. Logical domains (LDOM) is one of the para virtualization available with the Sun Sparc T1 and T 2 systems(Sun4v).   You can follow these simple steps to create your logical domains on your T1 and T2 systems. If you want to try it on x86 boxes , please use XEN Before going to the install , understand the  key components in LDOM's. Hypervisor Software piece works on the top of the hardware. Responsible for maintaining the isolation of domains. Interacts between the hardware  and the OS. Control Domain  Creats and manages the other logical domains ans service and services Service, I/O domains Provides the virtual network switch or virtual disk Guest Domain Uses the services from the services and I/O domains and is managed by the control domain. In broad term , can be  considere...

Many a times when storage team allocates storage from a EMC storage box , the disks are not labeled. Due to this you would see errors in the /var/adm/messages file like: Jan 31 16:50:48 geeklab Corrupt label; wrong magic number Jan 31 16:50:48 geeklab scsi: [ID 583861 kern.info] ssd12 at fp5: unit-address w20220080e517e28c,1: e8 Jan 31 16:50:48 geeklab genunix: [ID 936769 kern.info] ssd12 is /pci@12,600000/SUNW,qlc@0/fp@0,0/ssd@w20220080e517e28c,1 Jan 31 16:50:49 geeklab scsi: [ID 583861 kern.info] ssd8 at fp5: unit-address w20220080e517e28c,0: e8 Jan 31 16:50:49 geeklab genunix: [ID 936769 kern.info] ssd8 is /pci@12,600000/SUNW,qlc@0/fp@0,0/ssd@w20220080e517e28c,0 Jan 31 16:50:49 geeklab scsi: [ID 583861 kern.info] ssd2 at fp6: unit-address w20230080e517e28c,1f: e0 Jan 31 16:50:49 geeklab genunix: [ID 936769 kern.info] ssd2 is /pci@13,700000/SUNW,qlc@0/fp@0,0/ssd@w20230080e517e28c,1f Jan 31 16:50:50 geeklab scsi: [ID 107833 kern.warning] WARNING: /pci@13,700000/SUNW,qlc@0/fp@0,0/ssd...

Goal A Sun Microsystems platform, with a fiber disk as the boot disk, is dependent on the disk's World Wide Number (WWN) being included in its physical device path, in order for the system to boot properly. Below is a detail from a Sun Fire 280R system: /pci@8,600000/SUNW,qlc@4/fp@0,0/disk@w210000203746f423,0:a Physical Device Path /pci@8,600000/SUNW,qlc@4/fp@0,0/disk@w210000203746f423,0:a WWN If the primary boot device is replaced by a disk which has been ufsrestore'd (from a backup via ufsdump), then the WWN of this disk must be implemented into the Solaris Operating System device path, and must be associated with the correct  Solaris OS logical device. Solution Procedure for correcting device paths on the Sun Fire 280R: To show this as a working example, we copied c1t0d0s0 to c1t1d0s0 on a Sun Fire 280R via ufsdump and ufsrestore, then installed the boot-block. The two disks were switched, emulating the replacement of the primary disk. Note: The...

Symptoms During the boot sequence an error message with the following synopsis is reported on the console. panic[cpu< n >]/thread=< thread_id >: Can't invoke /etc/init, error < errno > where < n > represents the CPU number, < thread_id > represents the thread currently on the CPU at the time of the panic and < errno > represents an error code. For example, panic[cpu0]/thread=300004f9d00: Can't invoke /etc/init, error 2 The boot sequence is restarted and the message reported again resulting in a  panic cycle which will loop indefinitely. Cause Interpreting the Error Code: In order to arrive at a resolution it is necessary to understand what the error message is stating. The error code reported may be found in the /usr/include/sys/errno.h file, delivered with the "SunOS Header Files" (SUNWhea) package, and this should give a good indication as to the nature of the problem. Solution Since the system will ...