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Resuming downloads with the Microsoft download manager

by on Jan.08, 2015, under Windows

Right,

this seems to be a not-so-common situation, but imagine you have initiated a large download (a multitude of GBs ISOs from MSDN) and your download interrupted.

Or windows updates restarted the PC while you were having a cup’o’tea …

You are now asking yourself the question “How can I resume my downloads” ?

If you have noticed that you are indeed using the Microsoft File Transfer Manager (sometimes masked as Akamai technologies download tool or similar), then you will end up here on my blog looking for a solution.

If this window looks familiar, then read below:

Microsoft File Transfer Manager

1. Open Run

The Icon looks like this:

run

Vista+Win7+Win8: click “start” and just type “run”

XP: Press start and look for the right hand side option “run”

2. Type this:

c:\Windows\Downloaded Program Files\TransferMgr.exe

3. Find the program, go to Options and select “place a shortcut on the desktop”

Done!

The problem is, this tool is around since 2006 and in 2006 user experience was not a high priority (for some programs it is not today as well…).

So I hope this helped 🙂

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HP Probok 430 G1

by on Dec.03, 2014, under Windows

(if google or bing brought you here, scroll to the very bottom for a solution, I know what keywords you used 🙂 )

I recently purchased this laptop for my beloved life as a gift. I am not cheap when buying equipment, but as this will direcly be on the family budget, I needed do keep the WAF high (wife acceptance factor) by keeping the cost low.So if you are on the market for a 13.3 inch laptop which:

a) doesn’t weight a ton,

b) has VGA and HDMI output

c) mobile processor (not Atom)

d) non-gloss display

You end up buying the HP Probook 430. Specs wise it ticks all the right boxes, the little guy even has an extension port shared between the 3G UMTS card and mSATA. The 13.3 spots the usual 1368×768 resolution, but on a 13.3 that is the max you need for productivity and web surfing.

So I bought the Samsung 840 Evo SSD, installed win7 vanilla on it (licensed of course), tested the laptop with burn-in and was happy with how it behaves. Until we tried it on battery.

The laptop would randomly freeze and its display produced very strange image. If you have seen a VGA with broken sync buffer you will know what I mean. It just freezes.

And of course HP support was super helpful to tell me how this was a drivers problem, OS problem, my problem, everything else but the hardware. I didn’t buy that and went on the internet for “help”:

http://h30499.www3.hp.com/t5/Notebook-HP-ProBook-ZBook/hp-probook-430-g1-display-goes-blank-and-flashing/td-p/6428244#.VH7fncnET2A

It doesn’t take more than a few searches to see that more than one person is having such issues. But apparently different countries, different warranty budgets – mine wasn’t honored.

I tried the usual steps – firmware, drivers, clean boot, etc… but as one would expect, this did not help.

I checked the event log to find a multitude of EventID 37 source: kernel-power events right before the computer froze. But the Laptop did not overheat, CoreTemp was showing the right degrees, stress testing using HyperPi again did not show a direct dependency between the CPU load and the freezes. The suggestions to change the power plan to High Performance did the trick with the original i7 (Nehalem based), but nowadays the power regulators are on the CPU as well – I haven’t seen an improvement using the high power profile on a desktop machine…

Right before turning this rather good looking laptop to a pile of plastics, I tried the oldschool PC troubleshootingI applied the overclocker-style approach – go to BIOS and whatever looks suspicions – disable 🙂

 

(SOLUTION) In BIOS I ended up changing only 2 settings:

1) the memory for the display controller was set to 128 Mb fixed , changed to 512

2) disable the option to allow the CPU to dynamically change frequency (also known as Turbo)

In my case this was not big of a change since I only have a core i3 inside (non turbo CPU). On the graphics part – the machine has 8G RAM installed so assigning 0.5 for graphics isn’t much of a change. Subjectively the laptop runs much smoother now and most importantly – does not freeze anymore!

That is all HP should have said about this issue, but they did not. Hopefully this helps another one to save a few hours of head banging troubleshooting.

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How to get rid of JP, CH, KO effortless

by on Feb.03, 2014, under Windows

Recently I came across an interesting problem.

I have on my work “hate-this-slow-POS” laptop every other Microsoft product out there. This includes proof-typing on 3 Languages and there is an interesting side effect.

After windows update jumps in and installs whatever it does, I end up with a very large option of languages to choose from. These include Korean, Japanese, and TWO types Chinese. I wish I was fluent in any of those, but I am not. So I ended up looking for a solution.
I came across a number of posts from angry people that they have not configured any of those in their settings, so pretty much the language settings tab looks like this:

settings

But when you switch your language with your favorite key combo (Cntrl+Shift or Alt+Shift), then you end up clicking a lot more to cycle through this large list:

languages

Q: Why the H… is this happening to me?

A: Some smart MS guy decided to embed the integration of Asian languages into the startup process. That’s right – in the registry. No check is done if my computer actually uses the exotic languages, nor am I asked “do you want to install whatever-this-is?”.

Q: So how can I remove them?

A: I found the answer on a official Microsoft partner forum. I am unaware who is the original source to give credit for this finding, but here is how you can do that the easy way.

1. Download this file and execute the .reg from this .zip remoteExtraLang

2. Reboot.

3. Done.

This is a zip file which contains 2 files.

removeExtraLang.reg – just execute that (ignore all warning that this will harm your PC bla bla)

removeExtraLang.txt – this is the same file, in plain text.

Here is what the file does:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Run]
“IME14 KOR Setup”=-
“IME14 JPN Setup”=-
“IME14 CHS Setup”=-
“IME14 CHT Setup”=-

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Run]
“IME14 KOR Setup”=-
“IME14 JPN Setup”=-
“IME14 CHS Setup”=-
“IME14 CHT Setup”=-

It just finds the extra entries done by Windows Update (thanks again!) and removes them.

You could manually look in the registry and remove the entries yourself, but I am a lazy person and since this issue might reoccur, I just keep a copy of the reg file.

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Hyper-V Replicas = near-CDP ?

by on Mar.21, 2013, under Hyper-V, Server Core

So Hyper-V boosts another neat feature, also known as replicas.

Why would one need that? How exactly does it differ from HA Cluster and Backup?

I’ll try to answer those questions in a really quick-and-dirty way.

HA vs Replicas

HA means Clustering. Clustering means CSV (or SMB 3.0 file shares, but for the sake of full cluster solution, CSV is the way to go). This all copes well with the enterprise business model, where SAN is already in place or still something that can be bought. But for small/medium firms in the Bulgarian reality, where resources are scarce and requirements ridiculously high, SANs are not always preferred. Sometimes the OS Licenses needed for a HA deployment alone will cost more than the budget for the project.

So what can we do to avoid that? Microsoft aimed replication technology for data center fail-over functionality, but there is this aspect which can cope quite well in small deployments – replication.

What does this do? Once replication is enabled (very good Technet article ) you will see the VM in both primary and secondary Hyper-V hosts.

Here is a quick overview:

Primary host:

source

Secondary host:

dest

 

But if you try to start the machine on the secondary replica server, you will get this error:

err

 

Over LAN environments, replication speed is nothing short of impressive. I managed to saturate 1 Gb dedicated NIC for Replication on a very outdated hardware (AMD opteron dual core) with less than 30% cpu util.

Now this is not miraculous, but still quite a good figure.

From my observations, I can see that replication cycles occur every 5-10 minutes and for file-share servers this is near-CDP performance “out-of-the-box”. A further advantage for the Replication over traditional CSV is that one could keep a few versions back (thanks to VSS) and have an option to quickly bring a central file server back in production from a different server or even site within minutes.

Imagine you have 1,5 Tb of data and you need to be able to provide 99.999% uptime? On the first crash/outage of HW and the need to recover from a backup, you are already missing your SLA. So you have no options but to replicate.

If you are talking SQL however, you have no options but to run HA cluster OR use the standard master-slave SQL model. I am strongly advising against replication implementation in a SQL environment.

Again from the perspective of a small/medium company, it is doable to host the SQL on Microsoft Azure for example and delegate the management to the “cloud guys”. Why? Just calculate 20 perpetual SQL Standard 2012 licenses and you will see what will that cost you.

Again it always comes down to this – budget, goals, implementation.

But because Hyper-V server 2012 is freeware, and you don’t need to pay OS*nodes licesnes, you could easily build a small/medium cluster-like solution using really way less single points of failure while retaining performance.

Replicas vs Backup

Now I’ll start this with the following statement, so take it seriously:

Nothing is more important than a good backup

Snapshots and replica versions are not a backup, and they will never be. A backup is transportable, can be stored off or online, can be restored on a different machine etc….

Replicas offer some of the functionality of a backup, because they will provide independent snapshots, that are accessible up to a certain version back in time. But they are not transportable, nor to be stored offline, so you might use replicas for quick restore of the service, or VSS like primary recovery point for non VSS enabled guests (linux), but replicas alone should not be counted on for data recovery.

Replicas will do the job for a disaster recovery point in case something happened with the physical host. But in case of a VM corruption, it is highly likely that the problem would have replicated too, so a good backup strategy is a must.

Ok, as I said this one will be a quick one, but keep an eye for an update on the topic, as I dig in further into replica options and Powershell scripting on Hyper-V core hosts.

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CentOS 6.3 on Hyper-V – Storage performance and comparison

by on Feb.27, 2013, under Hyper-V, Linux

One of the first few things I noticed is the very good storage performance of the box. Windows Server 2012 introduced support for CentOS and made the integration services available as an installation RPM.

The physical hardware is not bad at all, but is no miracle either.

For this test I am using a Quanta Barebone with 1xXeon E5-1650 CPU loaded with 4×3.5 inch SATA 7.2k drives (HItachi Ultrastar A2000).

The System has a LSI9271 controller and is using the active backplane of the barebone, so this introduces an additional bottleneck which could limit the performance of SSDs, but using SATA drives, we are on the safe side with 6Gbps SAS. I have configured the drives in RAID5 and installed the OS on a separate RAID1 SSD array (hosted on separate controller), to minimize interference.

The Linux OS drive is placed on the SSD array as well. This leaves just the drive to be tested on the RAID5 SATA array. Some info – sdb is a Hyper-V VHD with 1900 Gb (why the odd number, I will explain in a different post), which is presented as an LVM member, for flexibility purposes. FS is ext4 on all tests.

I am using a relatively simple test

write :

time sh -c “dd if=/dev/zero of=ddfile2 bs=8k count=1M”

read:

time sh -c “cat ddfile > /dev/null”

Pure sequential read/write which relates to best case scenario when dealing with HDDs. This should show sheer bottlenecks, if any.

If I wanted to go deeper in my testing methodology, I would need to create a threaded test and monitor how performance scales with multiple threads. But that is “to do”, not a subject of this post. I was thinking about running bonnie++ since it displays easily understandable results, but as time pushed me, this will be the base for the future.

I used the very good system monitoring tool atop (ready RPMs available from CentOS Extras repo). Here is a snip out of atop on Hyper-V 2012.

Test1

Read:

LVM |     main1-app |  busy     90%  | read   37834  |  write      0 |  MBr/s 472.88 |  MBw/s   0.00  | avio 0.23 ms  |

DSK |           sdb |  busy     85%  | read   37834  |  write      0 |  MBr/s 472.88 |  MBw/s   0.00  | avio 0.21 ms  |

Write:

LVM |     main1-app |  busy     73%  | read      38  |  write1179003 |  MBr/s   0.01 |  MBw/s 460.73  | avio 0.01 ms  |

DSK |           sdb |  busy     71%  | read      38  |  write  47864 |  MBr/s   0.01 |  MBw/s 460.80  | avio 0.15 ms  |

 

What does this tell us?

Reading: LVM requests 37834 IOs/sec, average speed of reading is 472.88 Mb or 484229.12 Kb/sec, so the average IO size is 12.79 Kb

Moreover IO response time is below 2 ms, which lets the kernel think, OK I am on a high performance storage array, don’t throttle down. As a general thumb rule everything below 10 ms is really good, so 2 ms is a great result.

Writing: LVM requests 1179003 blocks to be written, but kernel knows to optimize those, and translates the blocks to 47864 HW  IOps on the HDD level. This means the ration between LVM writes and HDD writes is 24:1 .

Caching helps here, so we see a near zero latency. Average IO size is 9.85 kb/sec. This leads me to believe, that the hardware stripe size is 16k and is better suited for relatively small IO sizes. Real life analysis shows that 30% of IO requests are smaller than 16k, so this setting will surely help towards better performing storage for people that don’t specifically tune their storage subsys.

Attempting the same 100% read/write operations on another hardware box yields somehow different results, despite having identical spinners.

Test2

This is 6x 3.5 inch HDD SATA 7.2k array with hardware RAID controller (LSI 9260) with 512 Mb cache.

Read:

DSK |  cciss/c0d1 | busy    102% | read   19037 | write     31 | avio    0 ms

Write:

DSK |  cciss/c0d1 | busy    101% | read      11 | write   5917 | avio    1 ms |

Performance is 2 times lower, despite having 50% more drives in the array.

Lets attempt the same on a VMWare box, same hardware as in test1. Just plug a VMWare USB Flash drive, reformat the datastore to VMFS and lets see what it’s got.

Test 3

Read:

LVM |  test-lv_home |  busy    104%  | read   15892  |  write      6 |  MBr/s 198.61 |  MBw/s   0.00  | avio 0.63 ms  |

DSK |           sda |  busy    104%  | read   15892  |  write      9 |  MBr/s 198.61 |  MBw/s   0.00  | avio 0.63 ms  |

Write:

LVM |  test-lv_home |  busy    105%  | read       3  |  write 631219 |  MBr/s   0.00 |  MBw/s 246.57  | avio 0.02 ms  |

DSK |           sda |  busy    105%  | read       3  |  write   4947 |  MBr/s   0.00 |  MBw/s 246.67  | avio 2.02 ms  |

Reading: LVM requests 15892 IOs/sec, average speed of reading is 198.61 Mb/sek or 203376.64 Kb/sec, so the average IO is 12.79 Kb. Hmm the number is something we have seen before, haven’t we? But sheer performance is again very low compared to Hyper-V.
Why? (I am led to believe VMWare tells everybody on SATA drives just “Because F* you that is why”)
Ask VMWare. The HW is 100% VMWare certified and no 3rd party drivers have been installed.

Writing: LVM requests 631219 blocks to be written, but kernel knows to optimize those, and translates the blocks to 4947 HW  IOps on the HDD level. This means the ration between LVM writes and HDD writes is 127:1 .Caching helps here, so we see a near zero latency. Compared to Hyper-V the number of writes is very low, however so is performance. Average IO in this test is 51K. A whopping 51K – this partially explains why VMW is so slow. it most likely utilizes 64k stripe size in its VMFS, to decrease number of IOPS, thus offload CPU. But most expensive resource for small business is not the CPU. Its the IO!

Conclusion: If you want/need single server solution for virtualization (not even a cluster solution) or are just starting with virtualization, try Hyper-V. If you will be running LARGE infrastructures, and have 10+k Eur for a node, then VMW is a solution too.

But most importantly – know your hypervisor and size your IO subsys correctly.

 

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CentOS 6.3 on Hyper-V

by on Feb.21, 2013, under Hyper-V, Linux

Microsoft  (MSFT) are pushing hard their hypervizor as an alternative to the market leader VMWare.

Heck, they even certified it to run Linux (at the time of writing RHEL and CentOS), when the appropriate Integration Services are installed (see links in the footer).

So how does this work indeed?

In the next few posts about this, I will be sharing hands on experience using CentOS 6.3 installed on Hyper-V 2012 with integration services 3.4 (officially supported version at the time of writing).

 

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Hyper-V 2012

by on Feb.19, 2013, under Hyper-V

I have recently taken a different approach to server virtualization.
Until now I was using VMWare ESX for whatever virtualizatino project came up at any point in time. However as the requirements are getting more difficult and even larger in scale, I think I came to the point I need to start shifting towards different hypervizor or start planning big $$ for the hypervizor alone.

I will not discuss the advantages (or disadvantages) of each and every hypervizor out there, but will provide field track of my learnings when dealing with Hyper-V on Server 2012.

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Дипломна работа. 18 месеца по-късно.

by on Aug.01, 2012, under Дипломна

And she became what she became, remove remove.

А то стана тя каква стана, мани мани.

Малко така мога да опиша случилото се с моята дипломна. Тръгнах в една насока, после се обърнах в друга а накрая се нахендрих на тотално трето място. Както и да е.

Резултата е:

Erarbeitung von Methodologie zur Auswahl von Netzwerkkonfiguration mittels Link Aggregation Technologie und TCP Offloading

И последния да затвори вратата 🙂

 

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Реалността на Евро-зоната у БеГе то

by on Oct.25, 2011, under Обща

Докато си кисна да чакам (че у нас за жалост си има цяла дициплина спортно чакане) попаднах на следващият текст, който ме нкакара да се посмея и да прозра реалността, че макар и сатира е реално достижим и изпълним пъклен план:

 

2007 г.-България и Румъния приети в ЕС.

2015 г. Хърватия, Македония, Босна и Херцеговина и Турция са приети в ЕС.

2017 г .- Албания, Косово и Сърбия са приети в ЕС.

2018 г.- За първи път европейска институция назначава румънец на висок пост. Той назначава жена си, цялата рода на жена си, членове на семействата на техните съседи и най-добрите си приятели.

2019 г.- Служителите от балканските страни представляват 10% от европейската администрация.

2022 г.- Служителите от балканските страни представляват 60% от европейската администрация. Администрацията повишава заплатите тройно, въвежда гъвкаво работно време, южнославянските езици са на трето място сред “езиците на администрацията”. Поради стрес 90% от служителите на европейската администрация излизат в отпуск по болест. Най-многo заболявания са констатирани в периодите между 15 юни и 15 септември и 15 декември и 15 януари. Болните служители са забелязани в Алпите, Канарските острови и други места, известни като лечебни срещу стрес. Европейският парламент гласува закон, според който бюджетът на ЕС плаща за лечението на тези болести. По време на отпуските европейската администрация се движи от стажанти с временни трудови договори.

2025 г.- Балканците достигат 90% от администрацията. Македонците отново отказват да приемат еврото.

2026 г.- Високата цена на европейската администрация изисква драстични съкращения. Уволнени са всички белгийски граждани, служители на ЕС. Балканските служители на ЕС достигат 99.3% от общия брой.

2027 г.- Румъния успешно приключва приватизацията.

През 2028 г. Сърбия поема председателството на ЕС. През февруари Германия напуска ЕС. Месец по-късно тя е последвана от Франция и Финландия. До края на годината под албанско председателство напускат Великобритания, Белгия, Дания, Швеция, Холандия, Люксембург, Италия, Испания, Португалия, Австрия, Чехия,Литва, Латвия, Естония и Словения. Всички тези страни въвеждат строг визов режим за ЕС.

 

🙂

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Пътеводител на средностатистическия смартфон-потребител.

by on Sep.04, 2011, under Обща

Надявам се носителите на правата над Пътеводителя да не ме погнат заради долното плагиатство, но дори и да се пробват нямат какво да ми вземат.

Доказателството го нося на врата си от Понеделник до Петък в райнона на бизнес парк София 😉

Аз принципно съм заклет Windows Mobile фен, на всички версии до 6.5 включително. Имайте предвид четейки следващите няколко реда.

Реших, че е време да пообновя остарялото ми диамантче и се опитах. На два пъти. И успях! А в какво точно? Ще разберете в следващите няколко реда.

Първо харесах смартфон с операционна система Symbian и въпреки че разни хора ме предупреждаваха си реших – е кво толкова! И си купих това.

Първите 2 седмици зор докато свикна със симбиана, следващите 2 седмици кеф, колко е бърз телефона и оттам зор, колко много забива…

Е, не може да се отрече че камерата и клипчетата са доста добри, но като цяло старото ми диамантче ми върши същата ако не и по-добра работа. А е само 2 години по-старо. което си е точно една епоха според закона на Мур.

Добреее. Този път се набутах. Да опитаме отново. Остават Android и iOS. Понеже хората които ме познават, знаят че съм много анти “i” изделията заради философията на компанията “дизайн преди всичко” остана да прибегна до линукс базираният мноу готин, добре документиран и поддържан Android.

Или поне така си мислех в началото.

Та, един хубав вторник по време на типичният за IT специалист обяд състоящ се от бургер, картофки с кетчуп и кола реших за десерт да отскоча до Мултирама за едно телефонче.

И баш така направих – след около трийстетина минути в ръцете ми бе следващият заподозрян в търсенето на моето мобилно устройство: Motorola Defy

Така търпеливо разопаковах новото устройство, че служителят в Мултирама учтиво ми припомни, че застраховката важи от 00:01 часа на следващят ден.

2дни фурор – много е бърз, много е готин, на третия открих къде показва колко данни съм ползвал този месец. УЖАС! Без да съм правил кой знае какво, бях навътртял 200 мегабайта мобилен трафик. Айде 40 лева за трафик на провайдъра… Пих една студена бира по случая и разбрах как да разкарам постоянната свързаност на операционната система със интернет.

После се почнаха мъките със синхронизирането на контактите. Уж се смятам за грамотен потребител, но се оказа че Гугъл макар да предлагат всичко за без пари, искат да си платиш една добра сума за да имаш синхронизация между Outlook и тяхното устройство.

За връзка на устройството със мобилен компютър и синхронизация по кабел (както всеки нормален телефон го прави) и дума да не става. Евентуално срещу 39 евро има програми, които могат да помогнат, ама ако нещо се прецака не поемат отговорност.

Е, от хубава му страна пък има Angrybirds безплатно от Android market 🙂

Дообрее… май пак ще пия една студена и ще си рефлашна диамантчето, че най-простите неща се оказват най-сложни.

 

Успях в събирането на опит, дали съм успял да намеря смартфон-нирваната… май ще мине още време. А сега за събирането

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