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Showing posts from 2014

Google Sheets - inserting a static variable

Ever had a spreadsheet with set variables and wanted to use them in a formula but not have to type them over and over - just use the drag down feature and have it work? For example, if I had a formula where I wanted A3 to be present as part of it, and when I try to apply that formula to multiple cells the A3 becomes A4, A5, A6 etc? That's very annoying and up until now I've gone through and manually corrected it. Not any more! By putting a $ sign in front of the column ID and the row ID e.g. $A$3 - it won't change! It stays the same! OMGWTFBBQ! How long have I looked for this - I found the answer here: http://www.gcflearnfree.org/googlespreadsheets/14.3 - read up for more info! Yay!

How to restore a file with StorageCraft ShadowProtect

I've installed ShadowProtect on most of my clients' servers - it's a great product and if you're not using it for backups, then seriously consider it. One of our sub-contractors emailed me with some issues on restoring files so I thought I'd add my reply to him here as a quick cheat sheet: Log onto the server you need to restore the file from Open up the share where your backups are going Browse through the list of files and look for an .cd or .cw or .cm file around the correct date -cd.spi is a consolidated daily -cw.spi is a consolidated weekly -cm.spi is a consolidated monthly for a full listing see here: http://bit.ly/1mNLBps once you've found the correct file, right click on it and choose ShadowProtect Mount pick the defaults, except when it comes to the right date - the consolidated files have a list of possible days / weeks that you can choose - find the right one and click on it, then go Next mount the file as read-only unless you need read

Restoring Windows Sharepoint Services 3.0 - from disaster to victory beer!

Recently during a server upgrade I applied SP3 to Windows Sharepoint Services 3.0. This particular server had seen no love in a long, long time and it needed an absolute slew of updates. Naturally, Sharepoint broke and the site loved by my client was unavailable, as were many other services. The errors in the Eventlog were varied and painful, with lots of vague references to the apocalypse and the like. Naturally the logs get incredibly dense and I had another issue to contend with along the way - disk corruption. The ntfrs filesystem was reporting corruption and had taken out a chunk of the Sharepoint Wizard's configuration. That obviously had to be fixed first and was very worrisome - especially given I was working on a RAID1 disk. Normally, because the database needs an upgrade when you apply SP3, if it doesn't start straight up you can run the SharePoint Products and Technologies Configuration Wizard to repair it. Failing that, you can disconnect the farm, fix the datab

Upgrading DragonFlyBSD

I always forget how to do this, so I'm documenting it here. The DragonFlyBSD website is quite good and this all comes from www.dragonflybsd.org/docs/newhandbook/Upgrading Firstly, make sure the Makefile is present: # cd /usr # make src-create and wait while it does it's thing. Then we need to get the new source to build it: # cd /usr/src # git checkout DragonFlyBSD_RELEASE_3_8 (which is the current one) To find out what the current one is: # cd /usr/srv # git pull # git branch -r Then the build and upgrade process: # cd /usr/src # make buildworld # make buildkernel # make installkernel # make install world # make upgrade # reboot And it should all be done.

Adventures with Crashplan for backups

Recently through the excellent SAGE-AU ( www.sage-au.org.au ) I read about Crashplan. Produced by Code42 and found here:  http://www.code42.com/crashplan/ there were lots of positive comments about it. I've since deployed it in two separate locations - in the office and at home. I'm using the free implementation at the moment, which allows you a backup each day to a variety of places. They include a 30 day trial of their cloud backup solution - which is quite cheap for a home implementation - $165 / year for 2 - 10 computers. Check out the full pricing - but see what you can do with the free version:- At the office we have a straight Microsoft Windows based environment - Windows 7, Server 2008 R2 and a wee Windows 8 here and there. I've set up a Crashplan account using a single email address and installed it on almost all our machines. I have a Windows 2012 Server running in our virtual environment and I'm using it as the base for all the backups to go to. I added a

Securely wiping a hard disk in Linux

We're getting ready for some changes at home, and I thought I'd go through the old hard disk drives I have laying around. Once I'd managed to get them all together there are a staggering 25 to be wiped :( Usually I use the excellent Darik's Boot and Nuke (DBAN) which is awesome and very simple to use. In this instance, however, I'm also doing a fairly large data sort, archive etc and I need to have a functional machine to browse the disks prior to their destruction and reissue. Given my well know love for Linux Mint I executed an extensive (20 second) search of Google and came up with the following interesting information:- ATA, SATA and SSD's now have an internal way of securely wiping themselves! From a command prompt (elevate it to root for ease of use and make a note of your disk drives - if you wipe your system disk or data disk then it's game over!  Maybe use a LiveCD?) Go and check out  https://ata.wiki.kernel.org/index.php/ATA_Secure_Erase Th

Effects of travel on IT or What the hell do I take when I go overseas?

Recently I was on a trip to Jakarta, for pipe band of all things, however while there I still needed to keep up with my normal information load. My gear load out for work, or for holidays in Australia typically consists of two mobile phones (one work / one private), Google Nexus 7 (WiFi) and my 11" MacBook Air or 15" MacBook Pro. Taking all of this junk to Indonesia was unfeasible - although altogether the weight was under 3KG. I knew I would have my normal number of emails, still want to check my Feedly, Facebook, take photos etc. Keeping everything charged and good to go is a usual challenge, and I imagined it would be worse in Jakarta. Heading over, I took my HTC One X, Nexus and that was it. It was a gamble because I didn't want to unplug too much, but still needed to have access to a wide variety of data. I wondered at what other people travelling took and it seemed very much that this was fairly typical - tablet + mobile phone. Very few people seemed to have inclu

Amazon EC2 experiences

Recently I was reading about Arscoins and the usage they made of the free Amazon EC micro instances. Intrigues I decided to take a look. Amazon have a free tier of services. Minimal devices with enough hours to run all month. I chose an Ubuntu Linux instance and after running through a simple sign up had an instance ready to go. Using shared keys I could ssh to it (the only way to go) and I had set firewall rules so that only a couple of static addresses could get to it. Amazing! It was all up and going in about 15 minutes. Only a barebones server of course but enough for testing and the obligatory oooh from my co-workers. The instance is free for 12 months and I've set alarms so that in the case of exceeding usage I will be notified of any billing. They also offer Windows servers too and a variety of different operating systems. For the minimal amount of time involved it was a great experience. I strongly recommend treating the instance like a server and keeping it updated and s

Hubsan X4 H107C 2.4GHz Quad Copter Adventures

Recently I acquired from eBay one of these: It's a little tiny quadcopter! I first became interested, not so much in RC, but in quads after watching the TEDTalk by  Raffaello D'Andrea  - The astounding athletic power of quadcopters . I found this amazing and further found it amazing watching this from TEDTalks by  Andreas Raptopoulos : No roads? There's a drone for that . These devices are pretty awesome and could revolutionise the way we do so many things - from deliveries to rescue, precision work in the air, even video recording at the Winter Olympics! Given the X4's small size I've been constantly surprised by it's speed and stability - even under fairly strong wind conditions. Throughout our house we have ducted air and when the A/C is up high the breeze is really quite strong. The X4 handles it quite well - I never use more that 60% of power to push against the air currents and can keep it fairly steady. Comparatively my much larger RC helicopters s

Using Nagios and SNMP to monitor network devices

Usage: check_snmp  -H <ip_address> -o <OID> [-w warn_range] [-c crit_range] [-C community] [-s string] [-r regex] [-R regexi] [-t timeout] [-e retries] [-l label] [-u units] [-p port-number] [-d delimiter] [-D output-delimiter] [-m miblist] [-P snmp version] [-L seclevel] [-U secname] [-a authproto] [-A authpasswd] [-x privproto] [-X privpasswd] Note: the -c and -w (critical and warning ranges respectively) reflect ranges differently depending on if you want a critical to be low (under 10 for example) or high (over 90). In the former case, say the Signal Level of a microwave device you are monitoring is critical when under 10% and warning under 20% then the format of the -w and -c would be:             -w 25: -c 10: If on the other hand you are looking at Signal to Noise ratio where warning is 50 dB and critical is 75 dB then the command would be:             -w :50 -c :75 If you have say a table where numbers translate to other things,

How to fix Nagios3 external commands error

After installing nagios3 and trying to send it a command to reschedule a check or do some other external activity you may get the following error: Error: Could not stat() command file '/var/lib/nagios3/rw/nagios.cmd'! The external command file may be missing, Nagios may not be running, and/or Nagios may not be checking external commands. An error occurred while attempting to commit your command for processing. In order to fix it, do the following actions: Check that /etc/nagios3/nagios.cfg has: check_external_commands=1 Also check that command_check_interval=15s is uncommented and command_check_interval=-1 is commented like this: command_check_interval=15s #command_check_interval=-1 Check the path for command_file is OK. It usually looks like this: command_file=/var/lib/nagios3/rw/nagios.cmd Make sure that the user www-data is part of the nagios group - this is located in /etc/group Check permissions on the command file that we looked at above: # ls -l

How to update a single XenServer 6.2 host before adding it to a pool

You may find yourself in the position where you need to add a machine into a pool, a new host that is, and it's patching is well behind. Thankfully there is a relatively straightforward way to do this. You will need to have already downloaded and extracted the required files. On a computer with XenCentre installed run the following commands (assuming default install and Windows 7 / 8) Open a command prompt Win+r, then type cmd (or go to Start -> Run -> cmd and return) cd "C:\Program Files (x86)\Citrix\XenCenter" From here run: xe patch-upload -s server-ip  -u root -pw secret-password  file-name=c:\ username\Downloads\XS62ESP1\XS62ESP1.xupdate  and hit return. Make sure the items in italics  is replaced with your actual details. Once this finished, you'll get a long string of characters appear and that's the patch UUID. Normally when updating a pool we make note of that, but I've found another way that works just as well. Download puTTY -

XenServer 6.2 - installed on a USB drive and installed on an SD Card

In this post I want to talk about recent experiences I've had with XenServer 6.2 on USB drives and SD cards. In a particular situation, I was forced initially down this path due to specific hardware and lack of appropriate drives. The upshot is that it was entirely unsuccessful and here is why: Firstly, it's important to be aware that XenServer isn't all that happy being installed on these devices. After you install, you must boot back up on the XenServer CD and then (using ALT-F2) drop to a command line. To get XenServer to boot on USB do the following: From the command line do this:  # cat /proc/partitions this tells you what partitions there are that XenServer can see. Typically you will see /dev/sda and it's children - /dev/sda1, /dev/sda2 etc. We want /dev/sda1 # mkdir /target create a temporary location so we can change our root directory # mount -t ext3 /dev/sda1 /target mount our existing /dev/sda1 partition to /target, giving us access to the

ShadowCraft ShadowProtect - Employee of the Month

The last two weeks have been absolutely awful. The IOmega NAS I mentioned in a previous post had a large number of things go wrong with it all at the same time, resulting in complete failure and total data loss. This also meant a significant amount of down time for a client and ridiculous amounts of stress for me. The good thing to come out of it was the performance of ShadowProtect. This backup solution far exceeded my expectations to the point where once the recoveries were completed we had only lost 10 minutes of work. Very little data was realistically lost, only time as we worked to recover it. The Recovery Environment was easy to use and the Hardware Independent Restore allowed me to recover virtual machine from VMware 4 ESX to VMware Player, a physical machine and also to XenServer 6.2 quite a remarkable feat really. I've had this client running in borrowed hardware for a week while we get new gear in. The snapshot capability, ease of restore and simply replication of back

Experiences with the IOmega ix12 NAS

One of my clients has an IOmega ix12 - a rack mounted, 12x3.5" bay NAS. This one in question is running 2.6.5.something firmware and has (or should I say had) 8 x 1TB disks in it. Today it dropped another one. The NAS has been set up with a RAID10 with total storage of 2TB (1.5 or so in reality). Although it has this redundancy, I can assure you it's not all that it's cracked up to be. In the main storage pool is a number of iSCSI drives shared out with various ESX servers. Sadly, the largest and most important of these iSCSI drives has an unfortunate tendency to vanish whenever there is a disk issue. Today one of the drives failed. No big deal right? RAID10 is tolerant of such faults usually. This one kept going except for the aforementioned large drive that disappeared like magic. After replacing the disk, impatiently waiting for it to rebuild and then attempting to reconnect the iSCSI drives I realised I still couldn't see it. The fix? Turn the NAS completely off,

VMware nightmares

After a great couple of days away I was called urgently to work - one of my client's networks was down and my colleague was stuck. The VMsphere client couldn't see the hosts, which couldn't see their datastores and the network had zero stability. Yay. Just wanted I wanted to come home to. The servers are running ESXi 4.1 that needs a few updates but the networks stability has always been a real issue for us. We took it over from some other chaps, solving a long series of issues with the servers and particularly the IOmega NAS. Throw in a database issue on one of the guest servers that kept the disk IO at absolute peak all the time and things were pretty tricky. All those things have been resolved, more or less, and the network had been fully functional for some months. So why did it change? Several reasons and I hope you take away from this some ideas for yourself. The NAS appeared to have dropped a disk and while it has a RAID10 set up, it paralysed the system (not at al

The pure awesomeness of Google Forms

As a Google Apps reseller it never fails to surprise me how many people love Forms. I swear, I could nearly sell Google Apps to people just based on Forms. If you've never used it, here is a quick run down of what it can do for you: create a web form very quickly and easily, choosing from a range of different responses including: time (duration and date) multiple choice checkboxes create separate pages based on responses autofill a Google Spreadsheet automatically create a summary of responses with a range of different graphs and information instantly embed it into websites email notifications of changes and updates make you more popular with friends (OK maybe not this one!) Some examples of how I use Google Forms: PC Audit capture make / model, RAM, CPU etc Job Audit bookings for jobs completion of job information Incident responses Seriously they are awesome and if you're trying to do any type of statistics about stuff, they are a terrific pl