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Sky Q Hub lights explained

Confused by the lights on your Sky Q Hub when glowing solid, flashing or even off? This article explains and how to troubleshoot common problems.

How to refresh Apps on your Sky Q box

If your Sky Q TV apps are missing or the app freeze 15-30 seconds after starting, then use these steps to try and fix the issue.

Troubleshooting a hung process

Using truss/strace is a simple method to verify if a running process is performing any activity or is in a hung state whilst making a system calls.

Using netstat to troubleshoot linux networks

netstat is a useful tool for checking your network configuration and activity. It is in fact a collection of several tools lumped together.

Repairing a Damaged ZFS Device

This article describes how to determine ZFS device failure types, clear transient errors, and replace a device.

Repairing a Missing ZFS Device

If a device cannot be opened, it displays as UNAVAILABLE in the zpool status output.

Clearing Linux memory cache and swap

Every Linux system has three options when clearing cache without interrupting any processes or application services.

NetBackup Disaster Recovery

The procedures in this article explain how to recover your data if the system disk fails on a NetBackup master server.

Solaris patch return codes - patchadd

When installing patches on Solaris, you may often see error codes or Exit/Return codes when the patch installation fails. These are the return codes.

Resolving NetWorker media database corruption

The scope of this post is to provide a procedure resolving a common issue whereby NetWorker does not recycle tapes due to index corruption.

Resolving NSR peer information errors

You may also see the error after the NetWorker client upgraded with the same host name which created a duplicate NSR peer information for the client.

Introduction to Troubleshooting SAM-FS/QFS

This article provides a basic overview of SAM-FS/QFS Components, basic SAM-FS/QFS Troubleshooting and a list of SAM-FS/QFS resouces.

Troubleshooting SEVM/VxVM 3.x

This article is designed to walk you through common VxVM problems allowing you to troubleshoot them.

Preventing a Solaris 'Ping of Death' attack

The Ping of Death attack, first seen in 1996, is achieved using the Internet control message protocol, or ICMP (hence the name ?Ping of Death?).

VxVM 5.1 exit codes

The majority of the VxVM utilities use a common set of exit codes, which allow programs to react to specific problems detected by the utilities.

Solaris Fault Management Architecture

Solaris Fault Management Architecture (FMA) introduces a new software architecture and methodology for fault management across Sun's product line.

Recovering from a lost password on the T3

A simple procedure which shows how to identify a Sun StorEdge T3 / T3+ Arrays existing password if it has been forgotten.

Troubleshooting NSR tunnel

The NSR tunnel resource enables NetWorker clients and storage nodes to communicate with a NetWorker server over a firewall

Solaris Run Control Scripts

Run Control (rc) scripts are used to start and stop processes at boot up and shutdown.

Process monitoring using prstat

The prstat statistics utility shows a top-level summary of the processes that are using system resources currently.

Troubleshooting ZFS Swap and Dump devices

If you need to adjust the size of the swap volume after installation on an active system, review the following steps. See CR 6765386 for more info

Basic VERITAS Volume Replicator Commands

Veritas Volume Replicator aides in an effective maintain a consistent copy of application data at one or more remote locations via data-replication

Move a NetBackup image catalog to new location

In preparing to move the NetBackup image catalog from one location to another, it is recommended to perform a full catalog backup beforehand.

Renaming a ZFS zpool

Renaming a zpool is not as intuitive as I would expect, but it is still pretty simple. However, we can accomplish this through a three step process.

How to find System Serial number from command line

Ever needed to obtain the serial number of a system without physically inspecting the hardware. Here's some command-line examples for various systems.

Reset lost Solaris root password using kmdb

Performing a Solaris root password recovery when neither local cd/dvd or jumpstart (netinstall) options are avilable.

Understanding LLTSTAT output

Veritas Cluster Server?s Low Latency Transport (LLT) protocol provides fast, kernel-to-kernel communication and monitors network connections.

Resumable ZFS Send Streams

The ability to resume an interrupted zfs send/receive data stream which is a representation of a snapshot is now part of Oracle Solaris 11.4

Monitor and Manage ZFS Shadow Migration

Using Shadow Migration is very easy; for example, we could migrate shared ZFS and UFS file systems through NFS or even through a local file system

Troubleshooting NetBackup frozen media issues

Frozen media is the media that NetBackup does not use for backups. NetBackup stops directing the backups and the archives to frozen media.

Troubleshooting 'too many open files'

Applications or servers can sometimes fail with an error indicating that there are too many open files for the current process. Most of the time.

Repairing QFS file systems with samfsck

Whilst it is allowed to repair a mounted SAM-FS file system, you are encouraged to run the command on an unmounted file system.

SAM-QFS Manager Logging

To generate a SAM-QFS Manager troubleshooting report, run the /opt/SUNWfsmgr/bin/fsmgr_report command to create the /var/tmp/fsmgr.overall.log file.

Recreating /dev/null in Solaris

A simple procedure to recreate /dev/null on a Solaris system using the mknod command to create a special character device.

VxFS bug manifests as a backup issue

There is a rather nasty bug in Vxfs 3.3.1 that appears to manifest itself into a backup problem.

Gracefully shutdown Solaris 9

This article shows how to gracefully shut down Solaris 9 from within the CDE, and from the Console Login.

Using the OBDiag Utility

The OBDiag utility is an OpenBoot program designed to help the system administrator run extensive hardware diagnostics on a Sun SPARC system.

Troubleshooting Raid Manager (RM6)

A collection of troublshooting tips for the raid manager software for controlling the Sun StorEdge A1000, RSM200, A3x00 storage arrays.

Installing Solaris boot blocks

This post discusses how to install the boot block on a Solaris system running either the older UFS file system or the newer ZFS root file system.

Clearing a stuck tape in NetWorker

This tape usually ends up in ready for writing or state. At this point there appears that nothing we do can unmount or free the drive

Client Index and Media Database Integrity

To verify the integrity of the NetWorker client file indexes use the nsrck command and to verify media database use nsrim.

Merging Legato NetWorker Servers

This document provides the necessary steps to allow Backup Administrators to Migrate or Consolidate several Legato NetWorker servers.

NetWorker ASC/ASCQ Error decode utility

Use ascdcode to translate ASC/ASCQ status codes into verbal messages without any documentation.

Sun Storage T3 DMP Failover FAQ

This FAQ should answer some of the basic questions on how failovers work on the StorEdge T3 array

Using psradm to enable/disable a processor on Solaris

The psradm utility changes the operational status of processors. The legal states for the processor are on-line, offline, spare, Faulted, and no-intr

Troubleshooting the SAM-FS Recycler

This document is designed specifically to aide the resolution when you encounter issues with the Samfs/QFS recycler.

Troubleshooting the SAM-FS Stager

An article designed specificall y to aide the resolution when you encounter issues with the SAM-QFS stager.

Restart SAM-FS Stager

This post simply provides the steps necessary to restart the SAM-FS stager cleanly

Solstice Backup Server Recovery (pre 6.x)

A procedure to recovering from the loss or corruption of a Solstice Backup servers critical files including the index, media index, and resource files

Moving a SPARCstorage Array between servers

Here are the steps necessary to ensure successful switch-over of a Sun Storage Array (SSA) between two Sun systems.

Solstice Disksuite (SDS) Cheat Sheet

Solstice DiskSuite is a software product that enables you to manage large numbers of disks and the data on those disks.

Firefox scrolling on Solaris

Solaris will try to paste the top most thing in your clipboard when you click your middle mouse button.

Instant Image Cheat Sheet

Simply put, the software takes a picture, and then tracks any changes made since the copy is made through the use of a bitmap.

Restarting ACSLS

To restart the Automated Cartridge System Library Software (ACSLS) Software, simply perform the following steps.

System Logging across different UNIX systems

This post provides brief differences in the log files used for System Logging of the most common versions of UNIX.

Veritas Volume Manager state flowchart

This diagram is derived from the Veritas Volume Manager (VxVM) Performance and Tuning course notes. Additional state paths have been added.

Faster SVM mirror resync

There are two way to change block size to get quickly synchronized disks in mirrored system

XP Tweaks

Here, we've assembled 10 fast n' easy tweaks for any PC that break the factory mold and improve performance.

Clearing GPG BADSIG errors during update

During a test build of Ubuntu 15.10 I suddenly received the following error when refreshing the packages from the repository.

Using the truss command on Solaris

The truss command is used to trace system and library calls on a Sun or Sequent system. Which is similar to strace on Linux based systems

Listing avilable Solaris 10 services

Under Solaris 10 we use the svcs command to provide information about services, including their status.

Troubleshooting common NFS errors

Over the years I have seen some of the most common NFS Error/Issues which occurs in very common now and then to most of Solaris system admins.

Veritas NetBackup cheat sheet

This a quick cheat sheet of the commands that can be used when using Veritas NetBackup

Testing ping with jumbo frames

Depending on the OS you are running determinas which command and options to use in your testing.

Troubleshooting various NFS errors

Identifying and solving a problem is called troubleshooting, which is arguably the most difficult task in any area of computers. NFS is no exception.

Locating a ZFSSA failed component

A simple how-to article providing the steps necessary to locate a failed compaonent of a ZFS Storage Appliance using both the BUI and CLI

NetWorker no matching devices error

No matching devices for save of client NetWorker_Server; check storage nodes, devices or pools.

Unable to open FTP links in Mozilla Firefox 89

Mozilla has recently announced Mozilla's Firefox web browser won't support the FTP protocol from Firefox 90 onward.

Using Event Viewer for Hyper-V troubleshooting

Almost all events on Hyper-V are logged in Event Viewer, however they are divided between different event logs.

Troubleshooting NetWorker authorisation errors

This article provides a list of possible causes and resolutions for error messages that are related to NetWorker server authorization issues.

Managing Computers Remotely with the MMC

Managing a remote system using the Computer Management console, you must launch the console with an account that has administrative credentials.

What is the pathownerignore file?

This article describes the purpose and function of the pathownerignore file

Troubleshooting NetWorker pool attributes

In order for NetWorker to determine the volume to use, the pool criteria have to match exactly.

How to force NetWorker to clean a tape drive

Best practices suggest that auto-cleaning within NetWorker be turned off and allow the library to perform that task

How to run SPcollect on EMC Navisphere

This article provides the simple steps needed to gather SPCollects from the EMC Navisphere.

How to run SPcollect on EMC Unisphere

This article provides the simple steps needed to gather the SPCollects from the Unisphere Maager.

Setting up BMC event log file and size

When the cache becomes full, events are removed from it and placed in the repository file, which uses the following naming convention

Event log for BMC Patrol 9.5

As new events are created, older events are written to a log file called the PEM log.

Managing optical drives with Solaris 9 (LGTpa48374)

With Solaris 9, the volume Management daemon (vold) was changed so that it automatically attempts to manage all removable media devices.

Removing VxVM from a Solaris root disk

This post provides an example of how to remove VxVM from a Solaris root disk. The operating system is mirrored between the two devices.

NetWorker Management Console debug settings

irst set the debug level to display output for analysis. This can be done at the command line level or from within the GUI.

Sun Explorer Utility (SUNWexplo)

The Sun Explorer utility gathers information and creates detailed snapshots of a systems architecture and configuration.

How to panic a guest domain in Solaris 10

Forcing a panic of an unresponsive guest domain is simple by issuing an 'ldm panic-domain' from the primary domain.

What is the NetBackup Catalog?

The NetBackup Catalog is the internal database that contains information about backups and configuration and should be protected regulary.

Backing up the NetBackup Catalog

The NetBackup Catalog is the internal database that contains information about NetBackup backups and should be protected.

Dumping all resources into a single file

It's not uncommon to perform this task. In fact NetWorker does it everytime you run the NetWorker support nsr_support/nsrsup commands.

NetWorker 6.2 for Windows RAP improvement

Beginning with NetWorker 6.2, Legato introduces a new organisation of NetWorker's configuration database from nsr.res into nsr/res/nsrdb.

What is the NetWorker Common Device Interface (CDI)

CDI was introduced with NetWorker 7.4SP3 to provide a generic passthrough solution for all operating systems to control tape and status collection.

Data Domain system clock

When using AD mode for CIFS access, the data domain system clock time cannot differ by more than five minutes.

Resolving OST backup failures

This article lists steps on how to resolve data domain connection failures with OST allowing storage partners to deliver backup and recovery solutions

Testing network bandwidth using the NET IPERF command

This article describes how to collect and use network throughput measurements which are used for evaluating the performance of specific services

CloudBoost Disaster Recovery

If the CloudBoost appliance encounters a failure you must deploy a second CloudBoost appliance to restore the metadata from backups in the cloud.

What is the NetWorker rap.log

The RAP option tracks the history of additions, deletions, and modifications to a NetWorker resource or resource attribute.

Configuring link based IPMP on Solaris

IP network multipathing (IPMP) provides a mechanism for building redundant network interfaces to guard against failures with network interfaces.

Troubleshooting CIFS share backup failures

nsrexecd starts as a service under the SYSTEM account which normally does not have the correct security credentials to access the CIFS share.

stop/start syslogd on Solaris (updated)

syslog is an important facility need in all enterprises. We as sysadmins look at syslogs as a critical source to troubleshoot performance issues

Fixing ILOM command errors

There has been more than one instance when the Sun ILOM was not responsive to commands or were throwing errors

How to verify if LDom services are started

A short article on troubleshooting Solaris LDoms. Most LDom issues can be easily resolved by looing at the error messages.

Which Solaris package installed this file?

If you have a file and need to know the package that installed the file on the system then using pkgchk should help.

Restoring original Solaris file permissions

In the event of drastic file permission or ownership changes, it is possible to restore the original permissions of the file(s)

RM6 raid error code descriptions

This document describes the various RM6 error codes returned by the Series 3 RAID controllers and grouped accordingly.

RM6 Hardware Reset

This post provides steps needed to restart the configuration of an Sun StorEdge A1000 or Sun StorEdge A3x00 storage array back to factory defaults.

Basic Solaris Network Troubleshooting

Troubleshooting potential Solaris network services and issues using standard everyday tools ping, snoop, netstat and nfsstat.

Deleting invalid entries in NBU job monitor

Because the bpjobd.act.db file contains active and queued jobs, deleting it will only remove the unwanted job, since no other jobs were running.

How to analyze NetBackup unified logs

For legacy NetBackup logs which is located under /usr/openv/netbackup/logs , below numbers can indicate to you the severity when troubleshooting.

NetWorker Startup variables with nsrrc

Starting with NetWorker 8.0, NetWorker uses the /nsr/nsrrc file to define environment variables at NetWorker startup.

NetWorker recover completion query program (nsrrecomp)

The nsrreccomp command is used to query the NetWorker server jobs database and the recover log files in order to display a recover completion report.

Renaming a NetWorker server with nsrclientfix

This post provides a simple procedure that allows you to rename a NetWorker server using the nsrclientfix command.

Resolving NetWorker duplicate volume names

This can occurs when Relabelling existing or new media via the command line or using the GUI where cartridge barcode differ to the internal label

Troubleshooting NetWorker VSS errors

When VSS fails it can sometimes mean that you are unable to create a disk image or backup open files with EMC NetWorker

Setting the NOTSCAN flag on a volume in NetWorker

nsrim is unable to remove expired savesets which prevents data domain from performing housekeeping and prevents removing any data from the volumes

NetWorker Client Index Management

This article will illustrate the tools, concepts and techniques that you can use to develop your own custom NetWorker index management procedure.

Troubleshooting ZFS

Most ZFS errors I've experienced generally fall into one of three categories. missing devices, damaged devices and data corruption.

ZFS Hardware Maintenance

Once the drive has been physically replaced, run the 'zfs replace' command against the device to allow it to be brought back online.

openSUSE Quick Reference Guide

This article provides a quick reference guide for the open SuSE operating system

How to bypass BIOS Passwords

BIOS passwords are used to either prevent a user from changing the BIOS settings or to prevent the PC from booting without a password

Verifying Solaris 11 version

To check your software to see if they meet minimum version requirements for installation you can use the uname comand, however...

Oracle VM 3.4 Server Log Files

The Oracle VM Serverlog files you should check when troubleshooting problems with Oracle VM Server

Most commonly used XSCF commands

The eXtended System Control Facility Unit (XSCFU) is a service processor that operates and administrates both midrange servers

first login password change in WEBMIN fails

When creating webmin users and setting the flag change password after first login, 80% of the systems are successful

Detecting disks under Solaris

Ever needed to get Solaris to detect disks; the method depends on the version of Solaris. This article provides a how to

Troubleshooting Solaris memory usage

With Solaris 9 and later, comes an extremly nice mdb command for checking how much memory is used in kernel, and how much is used in user space.

Using the Hyper-V Best Practices Analyzer

The Best Practice Analyzer for Hyper-V has 74 scans to identify which settings are not configured, based on the Microsoft documentation and practices.

NetWorker Media database scavenging

Media database scavenging is simply a way to force Legato NetWorker to rebuild the media database header files.

Changing OLDAUTH setting on a NetWorker client

Use this procedure to switch from nsrauth to oldauth authentication on the backup server for the client exhibiting the problem.

Resolving NetWorker Archive and Retrieve issues

This post simply provides a method on how to troubleshoot various problems you may encounter with Legato NetWorker archive and retrieve.

Legato NetWorker diagnostic tools

Legato NetWorker includes a script called nsr_support that generates an exhaustive diagnostic report.