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Fallout 4 Laggy Mouse

December 24th, 2015 No comments

Bought Fallout 4 and so far have lost hours on it.
There’s a number of peopel complaining that the PC version has serious mouse-lag issues -which I agree with.

It turns out I just had an old rubbish low resolution mouse -and stupidly I didn’t think hardware would make any difference. Big thanks to a friend for setting me straight on that.

If you’re having slow mouse issues in any modern game, then try spending £20 on a cheap high-resolution gaming mouse before suffering or complaining any longer. The TeckNet M008 is cheap and seems reasonable (if a little large)

Categories: Gaming, HardWare Tags:

CentOS 6 libevent multilib issues

June 24th, 2015 No comments

Trying to run a `yum update` on a CentOS 6.4 box was giving multilib errors and failing horribly (this is after sorting out the epel repo ssl problem). After much faffing I finally resolved1 it.

First, the error:

[[email protected]~]# yum update
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
epel/metalink | 21 kB 00:00
* epel: anorien.csc.warwick.ac.uk
* remi: remi.check-update.co.uk
* rpmforge: ftp.nluug.nl
epel | 4.4 kB 00:00
epel/primary_db | 6.6 MB 00:04
Setting up Update Process
Resolving Dependencies
–> Running transaction check

< -- Packages snipped for berevity, full output is at the bottom of the post -->

–> Finished Dependency Resolution
–> Running transaction check
—> Package kernel.x86_64 0:2.6.32-279.14.1.el6 will be erased
–> Finished Dependency Resolution
Error: Multilib version problems found. This often means that the root
cause is something else and multilib version checking is just
pointing out that there is a problem. Eg.:

1. You have an upgrade for libevent-devel which is missing some
dependency that another package requires. Yum is trying to
solve this by installing an older version of libevent-devel of the
different architecture. If you exclude the bad architecture
yum will tell you what the root cause is (which package
requires what). You can try redoing the upgrade with
–exclude libevent-devel.otherarch … this should give you an error
message showing the root cause of the problem.

2. You have multiple architectures of libevent-devel installed, but
yum can only see an upgrade for one of those arcitectures.
If you don’t want/need both architectures anymore then you
can remove the one with the missing update and everything
will work.

3. You have duplicate versions of libevent-devel installed already.
You can use “yum check” to get yum show these errors.

…you can also use –setopt=protected_multilib=false to remove
this checking, however this is almost never the correct thing to
do as something else is very likely to go wrong (often causing
much more problems).

Protected multilib versions: libevent-devel-2.0.19-1.rhel6.x86_64 != libevent-devel-1.4.13-4.el6.i686
Error: Protected multilib versions: libevent-1.4.13-4.el6.i686 != libevent-2.0.19-1.rhel6.x86_64
You could try using –skip-broken to work around the problem
You could try running: rpm -Va –nofiles –nodigest
[[email protected]~]#

damn that libevent. This probably isn’t helped by the fact we’ve got a handful of 3rd party repos in use.
The PostgreSQL repo actually includes compat-libevent14 which seems to fulfil our needs, so here are the steps to sort everything out:

Read more…

 


  1. I hope I resolved it, it’s going into production in the morning

 

Categories: CentOS & RHEL 6 Tags:

CentOS 6 EPEL & YUM issues

June 24th, 2015 No comments

when trying to update an older CentOS 6.4 box, I was getting hte following errors:

[[email protected]~]# yum update
Loaded plugins: fastestmirror
Determining fastest mirrors
Could not get metalink https://mirrors.fedoraproject.org/metalink?repo=epel-6&arch=x86_64 error was
14: problem making ssl connection
* epel: mirror.bytemark.co.uk
* remi: remi.check-update.co.uk
* rpmforge: ftp.nluug.nl
…………

Other places in the internet have suggested editing /etc/yum.repos.d/epel.repo and changing the URL from https://…. to http:// (removing the SSL). This does actually work, but it doesn’t seem very clever.

After lots of going round in circles and then some more clever diffing (`curl -v` is your friend) I realised that the SSL CAs on the box were out of date so it fails to validate the mirror list. And there’s a very easy and correct fix:

yum update ca-certificates

After doing the above epel and everything else is much happier.

Note, on my box, the following deps are also updated:

=================================================================================================================================
 Package                            Arch                   Version                                 Repository               Size
=================================================================================================================================
Updating:
 ca-certificates                    noarch                 2015.2.4-65.0.1.el6_6                   updates                 1.3 M
 nss                                x86_64                 3.18.0-5.3.el6_6                        updates                 856 k
Installing for dependencies:
 p11-kit                            x86_64                 0.18.5-2.el6_5.2                        base                     94 k
 p11-kit-trust                      x86_64                 0.18.5-2.el6_5.2                        base                     71 k
Updating for dependencies:
 nspr                               x86_64                 4.10.8-1.el6_6                          updates                 113 k
 nss-softokn                        x86_64                 3.14.3-22.el6_6                         updates                 262 k
 nss-softokn-freebl                 x86_64                 3.14.3-22.el6_6                         updates                 167 k
 nss-sysinit                        x86_64                 3.18.0-5.3.el6_6                        updates                  45 k
 nss-tools                          x86_64                 3.18.0-5.3.el6_6                        updates                 433 k
 nss-util                           x86_64                 3.18.0-1.el6_6                          updates                  66 k

Transaction Summary
=================================================================================================================================
Install       2 Package(s)
Upgrade       8 Package(s)

Total download size: 3.3 M
Is this ok [y/N]:

To finish off I then run

yum clean all
yum makecache
Categories: CentOS & RHEL 6 Tags: ,

Cisco PacketTracer install Linux

January 22nd, 2015 3 comments

Installing 32bit Cisco Packet Tracer 6 on 64bit ubuntu 14 causes headaches.
Here’s how to get it running -read more for the steps I went through to work this out and don’t just run commands blindly without understanding them.

# possibly magic quickfix

dpkg --add-architecture i386

apt-get update
apt-get install libc6:i386 libncurses5:i386 libstdc++6:i386 libssl1.0.0:i386 libssl-dev:i386 libssl1.0.0 libssl-dev libx11-dev:i386 libxrender-dev:i386 libfreetype6-dev:i386 libfontconfig1-dev:i386 libglib2.0-dev:i386 libqtwebkit4:i386

At this point, if you try and launch /opt/pt/bin/PacketTracer6 directly you end up with missing ‘libQtWebKit.so.4’ errors. Launch `/usr/local/bin/packettracer` and it works (as the script sources the libraries it ships with).

On the flipside, linux mint (matte) runs it first time with no faffing about :)

Continue reading for why and how we got to this point.

Read more…

12 Days of GSM Christmas

December 16th, 2014 No comments

On the first day of Christmas,
I cloned OpenBSC
Need an MNC and MCC.

On the second day of Christmas,
compiling Osmocom-BB
Need legit spectrum usage,
And an MNC, MCC.

On the third day of Christmas,
can’t start OpenBSC
Reading 3GPP standards,
Still need some spectrum,
And an MNC, MCC.

On the fourth day of Christmas,
recursive dependencies
BSC controlling,
3GPP hurting,
Haven’t got a license,
Still need an MNC, MCC.

On the fifth day of Christmas,
A radio just for me
BTS Transmitting,
BSC Controlling,
3GPP Headaches,
Dialledback the power,
And an MNC, MCC.

On the sixth day of Christmas,
Runs almost stably
An MSC switched for me!
BTS transmitting,
BSC controlling,
3GPP madness,
Hidden in a cupboard,
And an MNC, MCC.

On the seventh day of Christmas,
Sectets broken me
Seven bit encoding.
MSC for switching,
BTS Transmitting,
BSC Controlling,
3G-PP!
Real attenuation,
And an MNC, MCC.

On the eighth day of Christmas,
battling radio frequencies
Eight are the timeslots,
Seven bit encoding,
MSC’s a-switching,
BTS transmitting,
BSC Controlling,
3G-PP!
Two AR-FCNs,
And an MNC and MCC.

On the ninth day of Christmas,
No more ISDN for me;
A-BIS over IP,
Eight are the timeslots,
Seven bit encoding,
MSC’s a-switching,
BTS transmitting,
BSC controlling,
3G-PP!
Two cells a-serving,
And an MNC & MCC.

On the tenth day of Christmas,
I need some sanity
Logging T-IMSI not the imsi IMSI
Um needs it’s A-BIS,
14 half-rate timeslots,
Seven bit encoding,
MSCs a-switching,
BTS unlocked!
BSC controls,
3G-PP,
Handover fails,
And need an MNC & MCC.

On the eleventh day of Christmas,
Time for secur-ity
A5/1 encryption is key.
TIMSI not an IMSI,
ABIS over IP,
AMR just fails,
Seven bits for texting,
MSC is switching,
BTS transmitting,
BSC controlling,
30-gig of specs,
PCS is 1900,
And an MNC & MCC.

On the twelfth day of Christmas,
Need interoperability
SS7 MAP for me,
A5/3 encryption,
TIMSI not an IMSI,
ABIS over IP,
7 timeslots free,
PDUs encoded,
MSC’s a-switching,
MS won’t you answer?
BSC online,
3GPP – explains it to me,
Two serving cells,
And an MNC & MCC!

 

I suppose I’m left trying to implement data for lent.

Windows system repair files

November 29th, 2014 No comments
sfc /scannow There is a system repair pending which requires reboot to complete. Restart windows and run sfc again.
try (but fails)
 
dism.exe /image:C:\ /cleanup-image /revertpendingactions
works:
 
del D:\Windows\winsxs\pending.xml del D:\Windows\winsxs\reboot.xml sfc /SCANNOW /OFFBOOTDIR=c:\ /OFFWINDIR=d:\Windows
Categories: Microsoft, Windows Tags:

Migrade

October 22nd, 2014 No comments

to Migrade:

Update the software and Migrate the hosting in one step.

Categories: Technology Tags:

Dell H200 SAS -Obscenely Slow

March 19th, 2014 2 comments

After installing VMware ESXi 5.5 RAID 1 and even RAID 0 performance was obscenely slow with a range of disks.

Much faffing about later and the tldr is basically the card disables the _ON DISK_ cache.

There’s much confusion online thinking the card has some sort of write cache; it doesn’t (though it does deal with SAS drives without requiring a licence (cough HP)). This is a cheap card, no write cache, no battery, none of that jazz (get a PERC 5e if you want some of that excitement). However it’s quite a capable direct sata/sas controller.

Y U go slo?

As default the card disables the cache that’s built into the hard drive itself (you’ll most likely remember it from such columns as (Buffer) Cache on PcPartPicker. I believe the correct term for this would be “on-disk write-buffer”. When looking at a drive for your desktop computer, anything that makes random writes bearable with spinning rust is a boon. If you have an unexpected power-off then the machine will reboot, do a disk check and you might have lost some of your browsing history, or even the last save of your essay… but probably not. Even if you do you’re not going to care.

When you’ve got a server doing mission critical work, when you tell the machine to commit to disk you expect it’s actually on the disk. Think a decent size database (100’s of gigabytes) with lots of sequential access. If you think stuff is safely in longterm storage and (for example) power off whilst it’s still in the cache, you’re likely to have all sorts of hellish corruption. The on disk buffer can also cause all sorts of interesting problems with RAID itself, especially when the disks start dying. To get over the performance hit expensive RAID cards leave the disk buffer disabled and have their own cache (which is usually in the hundreds of MBs if not gig). Known as a Write Cache these are (essentially) sticks of RAM with a battery attached.The card can promise the machine that the data is stored safely before it even spins the disks back up. RAM to act as fast and large temporary storage and the battery so that if the power suddenly dies, all the data in the RAM is still safe and can be written to the actual disks when power returns.

make it fast!

So by now you probably don’t give a damn about securing data integrity and you just want your datastore to be almost vaguely usable. It’s easy. Ish.

Find a Dell Open Manage Server Administrator liveCD or install it on your OS.  If you’re using ESXI then it’s doable but an insane ball-ache.1

Once booted/installed then go into the storage component, into your array and enable the disk cache. Reboot and find it’s almost usable.

-sorry about the lack of full instructions; I did this back in December so at this point you can either have it from memory or it’d just be a saved title in my drafts.

 


  1. you need to install the OMSA VIB on the ESXI host and then find another box to install just the web component server which you can then hit up with a browser. Maybe. It also seems to fail if the web component is on a VM on the same hardware. I will try and make myself go through it again and write some instructions…

 

Unlock Samsung S3 (i9300) in seconds

February 3rd, 2014 No comments

Trying to do some testing against a mobile network and wanted to use my UK T-Mobile S3; annoyingly as much as I could roam onto other networks, every time I tried to enter APN details (specifically non-matching MCC/MNC) they seemed to get automatically deleted when I saved them.

Rang up T-mobile and spoke to a lovely gentleman there, who told me I could get my phone unlocked for only £25 and with (upto) a months wait. As i didn’t relish waiting (and I’m sure the last time I spent 6 months not getting a code for my desire), I thought I’d find an easier option.

1 – Root Phone

2 -Install GalaxSim Unlock

3 -Pay GalaxSim £2.50 through the play store (T-mobile want £25)

4 -Be amazed and profit; all my APN settings are suddenly there again and it’s happy with all sorts of odd SIM cards.

5 -Be surprised it’s taken you this long to get round to it.

edit: So it turns out T-Mobile (UK) does something odd with their sim cards. Even in an unlocked phone (tested with a nexus 4), if you have a T-Mobile SIM installed then it won’t let you specify APN details that contain MNC/MCC that doesn’t match 234-30. Extremely annoying, especially as it took an hour on the phone to confirm this

Read more…

Categories: Android (G1), SGS3 GT-I9300, Technology Tags:

Network cloning disks like a pro

October 20th, 2013 No comments

So you want to clone a hard drive over a network, it’s ok, we’ve all been there. We want quick and easy and preferably some level of integrity insurance.

Boot systemrescuecd on box boxes and make sure both have an IP address and can ping each other. My example IPs are listed below -it’s worth pointing out that you should only do this over a trusted network, there’s no transport level security so potentially someone could be intercepting your stream.

Source: 192.168.0.5
Destination: 192.168.0.10

linux treats everything as files, so we can throw an iso image as easily as we can throw a hard drive, eg

#destination
nc -lp 1337 | dd of=/tmp/bigIsoFromSource.iso

#source
dd if=./MyBigIso.iso | nc 192.168.0.10 1337

Nice (nice). Now, you should be running md5sum on the files at both ends to make sure it wasn’t corrupted in transport, but if it’s a big file (or a disk partition) that could take a while. Wouldn’t it be good if we could split the streams (or split the pipe) so we could send the same read data from dd to both netcat and md5sum on the source, and the same on the destination? tee is our friend.

#destination
nc -lp 1337 | tee >(md5sum) | dd of=/tmp/bigIsoFromSource.iso

#source
dd if=./MyBigIso.iso | tee >(md5sum) | nc 192.168.0.10 1337

Cool beans, so now it gets checked on both sides of the network connection. It doesn’t let us see what’s going on though. you can send a `kill -USR1 <ddpid>` to dd’s process ID and it’ll print to stderror how far it’s gotten, but unless you stick it inside of wait it’s not automagically updating. For this we can use pipe viewer, which lets us see the state of data going through a pipe. If you’re feeling clever and know how big the file/partition/disk is, then you can pass the size to pv for even prettier output.

#destination
nc -lp 1337 | tee >(md5sum) | pv -s4.5G | dd of=/tmp/bigIsoFromSource.iso

#source
dd if=./MyBigIso.iso | tee >(md5sum) | pv -s4.5G |  nc 192.168.0.10 1337

and then just to be silly we’re going to compress it and calculate the hashes on both sides for both the raw input/output as well as for the compressed file that gets shoved over the network (hey, cores are cheap, right?)

#destination
nc -lp 1337 | tee >(echo -e “compressed: $(md5sum)’\n) | pv -s4.5G | bunzip2 | tee >(echo -e “raw: $(md5sum)’\n) | dd of=/tmp/bigIsoFromSource.iso

#source
dd if=./MyBigIso.iso | tee >(echo -e “raw: $(md5sum)’\n) | pv -s4.5G | bzip2 | tee >(echo -e “compressed: $(md5sum)’\n) |  nc 192.168.0.10 1337

*note nc under centos wants just the l and no p passing on the destination side, otherwise it errors out. so `nc -lp 13337` fails, but `nc -l 1337`works.

Categories: Linux Tags: , ,