Posts Tagged ‘application’

How to downgrade package with apt-get on Debian / Ubuntu / Mint Linux

Thursday, October 19th, 2017

how-to-downgrade-debian-package-to-an-older-version-debian_package-box

 

How can I downgrade a debian package to an older version with apt-get?

Downgrading a package in Debian is not frequently required but sometimes it is a must lets say a package you just upgraded fails to communicate properly to an application, in my case that's Ejabberd server which was working pretty well with Yaxim, Bruno or Xabber Mobile android application clients, unfortunately right after periodic apt-get upgrades I do with apt due to security upgrade of deb package ejabberd=2.1.10-4+deb7u1 to ejabberd=2.1.10-4+deb7u2 it messed up and even though it worked fine with Desktop clients such as Gajim and Pidgin, there was no Android application on my Phone with Android 4.4 which was able to communicate properly with the TLS encrypted Jabber server so my only option was to downgrade back to ejabberd=2.1.10-4+deb7u1.

I looked through duckduckgo.com a short URL is (ddg.gg) but I couldn't find the old deb file to downgrade so I was in a situation …

 Then I duckduck goed (I've recently stopped using Google as Google is collecting too much data and sharing with NSA) and I found following instructions on downgrade

——— 

If you have the version number, or the target release, apt-get supports choosing a particular version or target release. More details can be found on manual page of apt-get. It can also be accessed from terminal by typing man apt-get

sudo apt-get install <package-name>=<package-version-number> OR

sudo apt-get -t=<target release> install <package-name>

is the command to be run. This can be used to down-grade a package to a specific version.

It has been helpfully pointed out in the comments that

    apt-cache showpkg <package-name> – lists all available versions. (h/t Sparhawk)
    apt-mark hold <package-name> "holds" – the package at the current version, preventing automatic upgrades. (h/t Luís de Sousa )


In other words All I had to do is as root superuser is:
 

apt-get install «pkg»=«version»

OR

aptitude install «pkg»=«version»

Where «pkg» is the name of the package, and «version» is the version number.


So I just issued following cmd:

root@pcfreak:~# apt-get install ejabberd=2.1.10-4+deb7u1
Четене на списъците с пакети… Готово
Изграждане на дървото със зависимости       
Четене на информацията за състоянието… Готово
Предложени пакети:
  libunix-syslog-perl
Следните НОВИ пакети ще бъдат инсталирани:
  ejabberd
0 актуализирани, 1 нови инсталирани, 0 за премахване и 3 без промяна.
Необходимо е да се изтеглят 1795 kB архиви.
След тази операция ще бъде използвано 3699 kB допълнително дисково пространство.
Изт:1 http://ftp.uk.debian.org/debian/ wheezy/main ejabberd amd64 2.1.10-4+deb7u1 [1795 kB]


P.S. Sorry for the cyrillic for those who can't read it but it is standard messages that Debian does in package install time.

Analogously you can do it for any other newer package that upgraded, later on to prevent further security updates of the package you will have to put the package on hold, that's as easy as running:
 

root@pcfreak:~# aptitude hold ejabberd
No packages will be installed, upgraded, or removed.
0 packages upgraded, 0 newly installed, 0 to remove and 4 not upgraded.
Need to get 0 B of archives. After unpacking 0 B will be used.

 

Skype remove word completion / Howto Disable spellcheck autocorrect on Mac OS X, Android Phones Tablets and IPhone iOS

Tuesday, March 14th, 2017

How-to-disable-auto-correct-on-MacOS-X-android-and-iphone

I've recently upgraded my wife's Mac Book Air Mac OS X release from Mountain Lion to latest available OS X release Yosemite and after upgrade the old version of Skype used for about 3 years without any problems (except camera issues due to mac OS X bug the old post is here) stopped working (did crashed) on Skype launch so I took few minutes to upgrade Skype as well from Skype.com Skype for Mac official download page after the quick and unproblematic Skype re-install, Skype client was back to normal with a shiny new outlook and on a first glimpse all worked like a charm but …

On the next day when I took use of temporary the upgraded Mac Book Air with the fresh new OS X Yosemite and Skype's latest app to to do a quick login with my Skype credentials noticed a very annoying autocorrect (auto spelling)  Skype behavior on any new input text message.

I have to admit the idea of autocorrect feature on a system wide scale is great however quick keyboard typers like me who are used to type more than a letter per second use to type so quickly that occasinally you do errors which you're quick to fix but anyhow errors are automatically corrected in a way that you have to retype the whole word quite often which makes your typing a hellish experience. Then the same auto-correct feature becomes a terrible experience and on any device I notice this behavior I tend to remove it immediately.

I remember  the same dictionary auto-spell check / corect behavior was present on my Android run ZTE blade 3 mobile after first Mobile boot and also present on my current iPhone 5 iOS and thus the first thing I did once I start using it is to remove autocorrect (auto spelling) feature and relax the irritation of it.

Just in case if you need to disable Spellcheck auto-correct on Android Phone or Tablet do it from

Settings -> Language & input

android-phone-tablet-disable-autocorrect-spell-check

If you happen to be using also IPhone 5 as me or  Iphone 6 / 7 to disable AutoCorrect feature on SMSes / Skype / Viber and other applications do it from Phone's:

Settings -> General

disable_Turn_off_AutoCorrect_in_IPhone_iOS

Shortly I've noticed that the auto-correct feature does not only mess up your typing in Skype but also in Mail and TweetDeck and generally any open application where you can type on Yosemite.


I've took the time to investigate quickly what was causing the new feature that bugged me so much online and came to this nice little article How to turnoff autocorrect on Mac OS X 10.11 El Captain

As the article revealed to Turn off the autocorrect Mac OS X feature you I have to go:

Finder -> System Preferences

 

stop-skype-autocorrect-annoying-macosx-yosemite-system-preferences-menu-screenshot

Click on Keyboard -> Text
and turn  Autocorrect off by unchecking Correct spelling automatically

stop-skype-autocorrect-annoying-macosx-yosemite-system-preferences-keyboard-menu-screenshot

By doing this autocorrect spelling is disabled for all applications, however for some people it might be handy to leave the correct feature for Mail app or Microsoft Office (Microsoft Word / Excel) etc. and only turn off (disable) the autorrect feature per application side.

You can  do this in the separate Applications (of choise where you need auto spelling) from  Edit Menu under Spelling and Grammer and enable / disableCheck Spelling While Typing

stop-skype-autocorrect-annoying-macosx-yosemite-spelling-and-grammar-menu-screenshot


Tadam Enjoy ! 🙂

 

How to mount NFS network filesystem to remote server via /etc/fstab on Linux

Friday, January 29th, 2016

mount-nfs-in-linux-via--etc-fstab-howto-mount-remote-partitions-from-application-server-to-storage-server
If you have a server topology part of a project where 3 (A, B, C) servers need to be used to deliver a service (one with application server such as Jboss / Tomcat / Apache, second just as a Storage Server holding a dozens of LVM-ed SSD hard drives and an Oracle database backend to provide data about the project) and you need to access server A (application server) to server B (the Storage "monster") one common solution is to use NFS (Network FileSystem) Mount. 
NFS mount is considered already a bit of obsoleted technology as it is generally considered unsecre, however if SSHFS mount is not required due to initial design decision or because both servers A and B are staying in a serious firewalled (DMZ) dedicated networ then NTS should be a good choice.
Of course to use NFS mount should always be a carefully selected Environment Architect decision so remote NFS mount, imply  that both servers are connected via a high-speed gigabyte network, e.g. network performance is calculated to be enough for application A <-> to network storage B two sides communication not to cause delays for systems end Users.

To test whether the NFS server B mount is possible on the application server A, type something like:

 

mount -t nfs -o soft,timeo=900,retrans=3,vers=3, proto=tcp remotenfsserver-host:/home/nfs-mount-data /mnt/nfs-mount-point


If the mount is fine to make the mount permanent on application server host A (in case of server reboot), add to /etc/fstab end of file, following:

1.2.3.4:/application/local-application-dir-to-mount /application/remote-application-dir-to-mount nfs   rw,bg,nolock,vers=3,tcp,timeo=600,rsize=32768,wsize=32768,hard,intr 1 2


If the NTFS server has a hostname you can also type hostname instead of above example sample IP 1.2.3.4, this is however not recommended as this might cause in case of DNS or Domain problems.
If you want to mount with hostname (in case if storage server IP is being commonly changed due to auto-selection from a DHCP server):

server-hostA:/application/local-application-dir-to-mount /application/remote-application-dir-to-mount nfs   rw,bg,nolock,vers=3,tcp,timeo=600,rsize=32768,wsize=32768,hard,intr 1 2

In above example you need to have the /application/local-application-dir-to-mount (dir where remote NFS folder will be mounted on server A) as well as the /application/remote-application-dir-to-mount
Also on server Storage B server, you have to have running NFS server with firewall accessibility from server A working.

The timeou=600 (is defined in) order to make the timeout for remote NFS accessibility 1 hour in order to escape mount failures if there is some minutes network failure between server A and server B, the rsize and wsize
should be fine tuned according to the files that are being red from remote NFS server and the network speed between the two in the example are due to environment architecture (e.g. to reflect the type of files that are being transferred by the 2)
and the remote NFS server running version and the Linux kernel versions, these settings are for Linux kernel branch 2.6.18.x which as of time of writting this article is obsolete, so if you want to use the settings check for your kernel version and
NTFS and google and experiment.

Anyways, if you're not sure about wsize and and rise, its perfectly safe to omit these 2 values if you're not familiar to it.

To finally check the NFS mount is fine,  grep it:

 

# mount|grep -i nfs
sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
server-hostA:/application/remote-application-dir-to-mount on /application/remote-application-dir-to-mount type nfs (rw,bg,nolock,nfsvers=3,tcp,timeo=600,rsize=32768,wsize=32768,hard,intr,addr=1.2.3.4)


That's all enjoy 🙂

 

 

Increase tomcat MaxThreads values to resolve Tomcat timeout issues and sort

Friday, December 11th, 2015

Increase_Tomcat_MaxThreads_values_to_resolve_Tomcat_timeout-issues-and-sort

Thanks God, we have just completed (6 months) Migration few Tomcat and TomEE application servers for PG / PP and Scorpion instances from old environment to a new one for a customer.

Though the separate instances of the old environment are being migrated, the overall design of the Current Mode of Operations (CMO) as they use to call it in corporate World and the Future Mode of Operations (FMO) has differences.

The each of applications on old environment is configured to run in Tomcat failover cluster (2 tomcats on 2 separate machines with unique IP addresses are running) and Apache Reverse Proxy is being used with BalanceMember apache directive in order to drop requests to Tomcat cluster to Tomcat node1 and node2. On the new environment however by design the Tomcat cluster is removed and the application request has to be served by single Tomcat instance.

The migration completed fine and in the beginning in the first day (day 1) and day 2 since the environment went in Production and went through the so-called "GoLive", as called in Corporate World- which is a meathor for launching the application to be used as a production environment for customer, the customer reported TimeOut issues.

Some of the requests according to their report would took up to 4 minutes to serve, after a bit of investigation we found out, that though the environment was moved to one Tomcat the (number) amount of connections to application of end clients did not change, thus the timeouts were caused by default MaxThreads being reached and, we needed to to obviously raise that number. Here is the old Apache RP config where we had the 2 Tomcats between which the RP was load balancing:
 

BalancerMember ajp://10.10.10.5:11010 route=node1 connectiontimeout=10 ttl=60 retry=60
BalancerMember ajp://10.10.10.5:11010 route=node2 connectiontimeout=10 ttl=60 retry=60

ProxyPass / balancer://pool/ stickysession=JSESSIONID
ProxyPassReverse / balancer://pool/


As we needed a work around, we come to conclusion that we just need to increase Timeout on RP first so on Apache Reverse Proxy we placed following httpd.conf Virtualhost ProxyPass (directive) configs :

 

ProxyPass / ajp://10.10.10.5:11010/ keepalive=On timeout=30 connectiontimeout=30 retry=20
ProxyPassReverse / ajp://10.10.10.5:11010/

ProxyPass / ajp://10.10.10.5:11010/ keepalive=On timeout=30 connectiontimeout=30 retry=20
ProxyPassReverse / ajp://10.10.10.5:11010/


and following Apache Timeout directives options:

 

Timeout 300
KeepAlive On
MaxKeepAliveRequests 100
KeepAliveTimeout 15


Even though the developer tried to insist that the problem was in Reverse Proxy timeout config, they were wrong as I checked the RP logs and there was no "maximum connections reached" errors..

As you could guess what left to check was only Tomcat, after quick evaluation of server.xml, it turned out that the MaxThreads directive on old clustered Tomcats was omitted at all, meaning the default MaxThreads Tomcat value of 200 maximum connections were used, however this was not enough as the client was quering the application with about 350 connections / sec.

The solution was of course to raise the Maxthreads to 400 we were pretty lucky that we already had a good dedicated Linux machine where the application was hosted (16GB Ram, 2 CPUs x 2.67 Ghz), thus raising MaxThreads to 400 was not such a big deal.

Here is the final config we used to fix tomcat timeouts:
 

<Connector port="11010" address="10.10.10.80" protocol="AJP/1.3" redirectPort="8443" MaxThreads="400" connectionTimeout="300000" keepAliveTimeout="300000" debug="9" />


One note to make here is the debug="9" options to Connector directive was used to increase debug loglevel of Tomcat, and address="" is the local network IP on which Tomcat instance runs. As you see, we choose to use very high connectionTimeouts (because it is crucial, not to cut requests to applications due to timeouts) in case of application slowness.

We also suspected that there are some Oracle (ORA) database queries slowly served on the SQL backend, that might in future cause more app slowness, but this has to be checked seperately further in time as presently we were checking we did not have our Db person present.

 

Заповеди Блаженства (на Церковнослаянском языке, На Български and in English)

Tuesday, November 10th, 2015

Заповеди Блаженства (ТК Союз)

 

На церковнославянском языке по Мф 5, 3-11 

  1. Блажени нищии духом, яко тех есть Царствие Небесное
  2. Блажени плачущии, яко тии утешатся
  3. Блажени кротцыи, яко тии наследят землю
  4. Блажени алчущии и жаждущии правды, яко тии насытятся
  5. Блажени милостивии, яко тии помиловани будут
  6. Блажени чистии сердцем, яко тии Бога узрят
  7. Блажени миротворцы, яко тии сынове Божии нарекутся
  8. Блажени изгнани правды ради, яко тех есть Царствие Небесное
  9. Блажени есте, егда поносят вам, и ижденут, и рекут всяк зол глагол на вы лжуще, Мене ради: Радуйтеся и веселитеся, яко мзда ваша многа на небесех: тако бо изгнаша пророки, иже (беша) прежде вас.

Евангелски блаженства (Български)

  1. Блажени бедните духом, защото тяхно е Царството небесно.
  2. Блажени плачещите, защото те ще се утешат.
  3. Блажени кротките, защото те ще наследят земята.
  4. Блажени гладните и жадните за правда, защото те ще се наситят.
  5. Блажени милостивите, защото те ще бъдет помилвани.
  6. Блажени чистите по сърце, защото те ще видят Бога.
  7. Блажени миротворците, защото те ще се нарекат синове Божии.
  8. Блажени изгонените заради правда, защото тяхно е Царството небесно.
  9. Блажени сте вие, когато ви похулят и изгонят, и кажат против вас лъжовно каква и да е лоша дума заради Мене. Радвайте се и веселете се, защото голяма е наградата ви на небесата.

— Библията, Евангелие от Матей 5 глава 3-12 стих

The Beautitudes – The Sermon on the Mount (English)

Blessed are the poor in spirit: for theirs is the kingdom of Heaven. (5:3)

Blessed are those who mourn: for they will be comforted. (5:4)

Blessed are the meek: for they will inherit the earth. (5:5)

Blessed are those who hunger and thirst for righteousness: for they will be filled. (5:6)

Blessed are the merciful: for they will be shown mercy. (5:7)

Blessed are the pure in heart: for they will see God. (5:8)

Blessed are the peacemakers: for they will be called children of God. (5:9)

Blessed are those who are persecuted for righteousness sake: for theirs is the kingdom of heaven. (5:10)

In verses 5:11-12, the eight Beatitudes are followed by what is often viewed as a commentary—a further clarification of the eighth one with specific application being made to the disciples. Instead of using the third-person plural "they", Jesus changes to second-person "you":[1]

Blessed are you when people insult you, persecute you and falsely say all kinds of evil against you because of me. Rejoice and be glad, because great is your reward in heaven, for in the same way they persecuted the prophets who were before you.

Windows XP / 7, Minimize any program to system tray free software – RBTray, Trayconizer and Windows HideIT

Monday, January 5th, 2015

rbtray-screenshot1-on-ms-windows-minimize-any-application-systray-winblows
As Linux admin, I'm already aware of AllTray *NIX application able to send any application to GNOME / KDE tray.
But what If you have a program on Windows XP / 7 / 8,  that doesn't have a minimize to tray functionality and you want to send it to tray?
I.e. what if you want to send programs like Notepad (that doesn't by default go to win systray) to Windows  tray in order to prevent them mess up with other Open Windows minimized windows?

After a quick research on the topic I found these 3 – RBtray, Trayconizer, HideIt, Below is a very quick review on each

.

1. Minimize any Windows program to tray with RBTray

rbtray_windows-7-screenshot-minimize-any-application-to-tray-minimize-notepad
If you want to stick to open source (GPL) software a tiny free software proggie that does the trick is RBTray current latest RBtray is 4.3 release is download mirror is here.

To use RBTray you don't need to do anything, once program is unarchived from archive, once launched there will be no system application that it is running, but you can go to any minimized program (not in tray) and by clicking with right mouse button on minimize button you will the app minimize to tray.

Here is how RBTray works (taken from archive README file):

Installing:
Extract the 32-bit or 64-bit binaries (depending on your OS) to a
 folder, e.g.
C:Program FilesRBTray.  Double click RBTray.exe to start it.  If you want it
to automatically start after you reboot, create a shortcut to RBTray.exe in
your Start menu's Startup group.

Using:
Right click on any program's minimize button to minimize it to the tray.  To
restore, single-click the program's icon in the tray.

Exiting:
Right click on any tray icon created by RBTray and click Exit RBTray in the
popup menu.  Or run RBTray.exe with the –exit parameter.


2. Miminize any app to system tray with Trayconizer

trayconizer_screenshot-microsoft-windows-minimize-notepad
Trayconizer is the other tray minizer tool you might want to check out, Windows tray minize application a download mirror of Trayconizer is here. As of time of writing this post (current) latest Trayconizer version is 1.1.1.

Trayconizer allows you to minimize virtually any application to the system tray rather than having it take up valuable space in your taskbar. The screen shot to the left shows Trayconizer minimizing Notepad to the system tray. Trayconizer is definitely the tool of choice of system administrators who need to keep minimized windows program to system tray each time on boot as it can be easily run from command line.

Using Trayconizer is simple. To start Trayconizer on Notepad, you would execute: C:PathToTrayconizer.exe C:WindowsNotepad.exe.

You can create a shortcut in your Startup group to execute Trayconizer on a program that you use frequently but want to keep tucked out of the way in the system tray when you're not using it. There is even an option for starting the application initially in the minimized state.

Trayconizer will automatically shut itself down when you close the program you are Trayconizing. Additionally, multiple Trayconized programs are handled by a single instance of Trayconizer to avoid wasting system resources.

Trayconizer requires no DLL's beyond the base Win32 API libraries and will not store any entries in your registry.

3. Minimize any program to Windows systray with Windows HideIT

windows-hideit-minimize-to-tray-screenshot-send-any-running-windows-program-to-systray

Another good tool useful in hiding (minimizing) Windows programs which are lacking the minimize option embedded built-in is Windows HideIT.

Hideit official download website is here, note that with Hideit, Its pretty confusing to find where to download in (so to download look in the right upper corner for a download button) HideIT Download Mirror is here.

Hideit should be able to minimize any Application to sysytem tray, while Rbtray fails ith some. Both RBtray and Windows
HIdeIT will popup with a blue down-arrow on Tray icon once launched and you can show / hide minimized applications from there.

All RbTray, Trayconizer and HideIt tray minimizers should work on virtually all NT 4.0 Windows XP / 2000 / Vista / 7 / 8 though I haven't tested on all of 'em yet. If you happen to find it working on  Win NT 4.0 / 8 etc., please drop a comment.

How to split / rar in parts large data archive files on Linux and Windows – Transfer big files across servers located in DMZ rescticted areas

Friday, November 28th, 2014

how-to-split-rar-in-parts-large-data-archive-files-on-Linux-and-Windows-Transfer-big-files-across-servers-in-firewalled-restricted-areas

I was working on a Application Migration Project whose goal was to Install a business application called Asset Guardian and then move current company Data from the old server to the new AppServer.
F
or that purpose the company vendor Asset Guardian shipped to a Public access FTP, a huge (12GB) ZIP archive file which had to be transferred into a well secured DMZ-ed corporation network with various implemented Traffic Shaping Network policies, a resctrictive firewall allowing access to Internal Network only and to Few (Restrictive configured) Proxy Server IPs on port 80 and 8080.

One of the proxy servers allowed access to the Internet and I set this one and tried downloading the Huge Archive file  with the Windows 2012 server default browser Internet Explorer 10, though the download started it kept slow between ~ 300 – 500KB sec and when reached 3.4GB download failed. I tried resuming the download but as the remote Public FTP server where files resides doesn't support FTP RESUME function.
I thought it might be that Internet Explorer is badly managing the download so, I go forward and installed Portable Firefox (mirrored version 33.1.1 is here). Re-running download with firefox also failed, so the next logical step was for me to try downloading with Windows version of Wget (Wget) and with Portable Free Download Manager 3.9.14.1481 (mirrored here) using both of them was unable to complete download (probably due to firewall or Proxy screwing the proxy inspected traffic) thus I had to look for another way to copy the enormous archive into the company network.

To get around the issue I tried to download the file from FTP to another Server running Apache and tried re-downloading the big file archive (Asset-Guardian-data.zip) from Apache Webserver via HTTP protocol, this download method didn't work neither using plain HTTP protocol for download when downloaded file reached (3.4GB), thus I realized this is due to restrictive Proxy servers (dropping file downloads) bigger than  3.4GBs).

Then to be able to transfer the huge 12GB file, it seems the only left option was to to chop the big file on smaller file chunks and transfer them one by one.
In my case I had the Asset-Guardian-Files.zip transferred already to the Apache (Webserver) host which is running Linux so basicly the task was to Transfer Big archive file between the SuSE Linux Enterprise Server (SLES) 11 and Windows 2012 Server.

Quickesy way to do that is by using UNIX split command, i.e.:

split -b 1024m Asset-Guardian-Files.zip


The outputted files each 1GB are with naming (xaa, xab, xac, xad, xae, xaf, gaf etc.) in same folder where split command is run:

To later merge the files on the Windows 2012 server (copy) command is used:

copy /b file1 + file2 + file3 + file4 filetogether


In my case the command to issue on Win 2012 server was:

copy /b xaa + xab + xac + xae + xae + xaf + xaf + xag xah xai xaj xak Asset-Guardian-files.zip


This method to chop and transfer the file is most simple one and it doesn't require the two servers to have WinRAR or Console RAR / unrar installed.

If instead of Copy Huge File from Linux -> Windows host you need to copy too big file (lets say 100GB) between 2 Windows servers (Windows server host A and Windows server Host B – both situated in different firewall corporate networks) you will need to download to Win Host A and use Windows UNIX split equivalent tool called sfk (The Swiss File Knife) , sfk has port also for Mac OS so in case of need for need for migrating huge archive file from Mac OS X host it will serve as Linux's split – I've made SFK (current version) mirror here.

Another way to cut the 12GB file in parts and transfer to destination host via HTTP was to use rar (on the Linux host), then download the file on Win 2012 server and use Winrar Portable Free to extract the multiple files:

To make archive separate in parts set out to certain size out of a huge file with rar on Linux use:

cd /var/www
rar -a -v1000000k Asset_Guardian_Files.splitted.rar /var/www/Asset_Guardian_Files.zip

10000000Kbs = 10000000/1024 = 976MBs, hence rar produced parts will be sized to 976MB rar parts.

To find out archives check for *splitted*.rar in your /var/www

ls -al /var/www/*splitted*.rar
-rw-r–r– 1 root root 1048576 ное 28 18:34 Asset-Guardian-Files.splitted.part1.rar
-rw-r–r– 1 root root 1048576 ное 28 18:34 Asset-Guardian-Files.splitted.part2.rar
-rw-r–r– 1 root root 1048576 ное 28 18:34 Asset-Guardian-Files.splitted.part3.rar
-rw-r–r– 1 root root 1048576 ное 28 18:34 Asset-Guaridna-Filse.splitted.part4.rar

 

Then to download the files M$ Win 2012 server IE (http://my-linux-host.com/Asset-Guardian-Files.splitted.part1.rar, http://my-linux-host.com/Asset-Guardian-Files.splitted.part2.rar. etc.)

Thanks God, Problem Solved 🙂

xkill for Windows – Kill hanged programs with one click like in UNIX

Thursday, September 18th, 2014

Windows Xkill by Solo Dev logo kill easily hanged, crashed windows programs - Linux xkill for Windows alternative

I’ve used Linux as I’ve used it over the last 10 years and thus I’m so used to xkill that I consider it as a normal tool every modern operating system should have.

Since I’m forced to work on a Windows platform over the last 1 year, every now and then I have crashing / hanged apps Window which sometimes is hard to kill using Task Manager or command line tools like tasklist, taskkill or pstools – Windows Sysinternal tools cause you don’t know the exact process name of the Windows crashed application.

Thanksfully a good hearted guy SuprVillain made Windows Xkill program. Windows Xkill is portable app, so you don’t need to install it but simply download and run it.

windows-7-system-tray-xkill-screenshot-xkill-for-windows

Win-Xkill runs in system tray and has “kill mode” of operation, when Kill mode it is running Windowns Xkill operates exactly like UNIX’s xkill. The mouse pointer turns into Skull and Cross Bones, you point at a Window app you wanted to kill and it gets terminated.
Windows Xkill kill mode enabled killing a windows notepad app
Win Xkill kill mode, can be invoked using also a key press Control+Alt+Backspace as well as there is an option to leave xkill running in the background background, but disabling the tiny skull icon in systray from its interface.
Enjoy 🙂

Run native Internet Explorer 6 on latest Debian / Ubuntu Linux with IEs4Linux

Thursday, July 24th, 2014

Install-internet-explorer-on-debian-linux-IEs4Linux_logo.svg
If you're a GNU / Linux Desktop user like me and you have to administrate hybrid server environments running mixture of MS Windows with Microsoft IIS webserver running active server pages (.ASP) developed application or UNIX / GNU Linux servers web applications using Mono as a server-side language, often you need to have browser which properly supports  Internet Explorer Trident web (layout) renderer (also famous as MSHTML).

Having Internet Explorer on your Linux is very useful for web developers who want to test how their website works under IE.

Of course you can always install Windows in Virtualbox VM and do your testing in the Virtual Machine but this takes time to install and also puts a useless load to a PC ….

IES4 Linux is a Linux free (open source) shell script that lets you run Internet Explorer on your Linux desktop.

ies4linux scripts collection uses emulation with WINE (Wine is Not Emulator) emulator to run the native  Windows Internet Explorer thus before use it you have to install Wine.

There are plenty of tutorials online about ies4Linux, problem is as it is not updated and developed most tutorials doesn't work on Debian Wheezy / Ubuntu and rest of deb based linux distros.
This is why I decided to write just another ies4linux tutorial that actually works!

On Debian / Ubuntu / Mint Linux install via apt-get:

apt-get –yes install wine

Then with a non-root user download ies4linux-latest.tar.gz. Just in case ies4linux-latest.tar.gz disappears in future I've created also a ies4linux-latest.tar.gz mirror for download here

and unarchive tar archive:

wget http://www.tatanka.com.br/ies4linux/downloads/ies4linux-latest.tar.gz
tar -zxvf ies4linux-latest.tar.gz
cd ies4linux-*
./ies4linux

You will get:
 

IEs4Linux 2 is developed to be used with recent Wine versions (0.9.x). It seems that you are using an old version. It's recommended that you update your wine to the latest version (Go to: winehq.com).

You need to install cabextract first!
Download it here: http://www.kyz.uklinux.net/cabextract.php

To fulfill this requirement you will need to also cabetract package which is luckily part of Debian:
 

apt-get install –yes cabextract

On wine version 1.0 and onwards winprefixcreate has been changed to winecfg binary.
To prevent missing wineprefixcreate, errors during ies4linux installer run  its necessery to symlink as a workaround:
 

ln -sv /usr/bin/winecfg /usr/bin/wineprefixcreate


To continue with Internet Explorer ies4Linux installater run again:

./ies4linux

images/internet-explorer-for-linux-debian-gnu-linux-screenshot

/images/internet-explorer-4-linux-installer-debian-gnu-linu-screenshot

You will get the installer GUI window with selection option which Internet Explorer version you want. Choose between IE 5.0, IE 5.5 and IE 6. It is also possible to install IE 7 which is still considered beta version and is less tested and unstable, will probably lead to crashes. If you want to install also IE 7 check it as an option from Advanced menu.

/images/ies4linux-internet-explorer-installer-debian-gnu-linux-screenshot

If you get permission errors after running ies4Linux gui installer to solve that chown recursively directory to the user with which you will be running it:
 

chown -R hipo:hipo ies4linux-2.99.0.1

 

Internet Explorer for Linux downloader, will connect Microsoft.com website and download DCOM, MCF and various IE required .CAB files.

If you get some ies4linux GUI installer unexpected crashes you can try to download all required IE binaries, surrounding files and flash player using no-gui installer with cmd:
 

./ies4linux –no-gui –install-corefonts

IEs4Linux 2 is developed to be used with recent Wine versions (0.9.x). It seems that you are using an old version. It's recommended that you update your wine to the latest version (Go to: winehq.com).

IEs4Linux will:
  – Install Internet Explorers: 6.0
  – Using IE locale: EN-US
  – Install Adobe Flash 9.0
  – Install MS Core Fonts
  – Install everything at: /home/hipo/.ies4linux
[ OK ]

Downloading everything we need
  Downloading from microsoft.com:
   DCOM98.EXE
   mfc42.cab
   249973USA8.exe
   ADVAUTH.CAB
   CRLUPD.CAB
   HHUPD.CAB
   IEDOM.CAB
   IE_EXTRA.CAB
   IE_S1.CAB
   IE_S2.CAB
   IE_S5.CAB
   IE_S4.CAB
   IE_S3.CAB
   IE_S6.CAB
   SETUPW95.CAB
   FONTCORE.CAB
   FONTSUP.CAB
   VGX.CAB
   SCR56EN.CAB

  Downloading from macromedia.com:
   100% swflash.cab

  Downloading from sourceforge.net
   0%   webdin32.exe[ OK ]bdin32.exe

Installing IE 6
  Initializing
  Creating Wine Prefix
Your wine does not have wineprefixcreate installed. Maybe you are running an old Wine version. Try to update it to the latest version.

To fix the error:

Your wine does not have wineprefixcreate installed. Maybe you are running an old Wine version. Try to update it to the latest version.

vim lib/functiions.sh

Go to line 36 (Type :36 in vim)

Line:

wine –version 2>&1 | grep -q "0.9." || warning $MSG_WARNING_OLDWINE

Has to be changed to:

wine –version 2>&1 | egrep -q "0.9.|-1." || warning $MSG_WARNING_OLDWINE


Also you need to substitute wineprefixcreate to wineboot (if you haven't already symlinked wineprefixcreate to winecfg – as pointed earlier in article.

To do so make following substitution in lib/install.sh and in lib/functions.sh

cp -rpf lib/install.sh lib/install.sh.bak; cat lib/install.sh |sed -e 's#wineprefixcreate#wineboot#g' > lib/install_new.sh; mv lib/install_new.sh lib/install.sh

cp -rpf lib/install.sh lib/functions.sh.bak; cat lib/functions.sh |sed -e 's#wineprefixcreate#wineboot#g' > lib/functions_new.sh; mv lib/functions_new.sh lib/functions.sh


Also it is necessery to change default corefonts download url which points to sourceforge but is failing. I've made mirror of corefonts files here
 

cp -rpf lib/install.sh lib/install.sh.bak; cat lib/install.sh |sed -e 's#http://internap.dl.sourceforge.net/sourceforge/corefonts/#www.pc-freak.net/files/corefonts/#g' > lib/install_new.sh; mv lib/install_new.sh lib/install.sh

Re-run the ies4linux console installer:
 

 ./ies4linux –no-gui –install-corefonts

….
Es4Linux installations finished!

On installation success you should get output like this
Hopefully you will see no errors like in my case, if you get the corefonts download error again re-run the installer and it should succesully download the files.

To then run ies4linux:

~/bin/ie6


internet-explorer-ies4linx-running-on-debian-gnu-linux-screenshot
Though Ies 4 Linux is good for basic testing it is not psosible to use the browser for normal browsing because its a bit buggy and slow.

By default Internet Explorer 6 behavior is to prompt security alert on various actions, though this might be useful for debugging it is really annoying so I personally disabled those by decreasing from:

Tools -> Internet Options -> Security -> (Security Level)
I've decreased it from Medium to Medium-Low

ies4Linux was not developed since 2008 and as of time of writting ies4linux official project website seems abandoned.

 

Fix MySQL connection error – Host ” is blocked because of many connection errors; unblock with ‘mysqladmin flush-hosts’

Wednesday, July 2nd, 2014

fix-mysql-too-many-connection-errors-explained

If you get a MySQL error like:

Host '' is blocked because of many connection errors; unblock with 'mysqladmin flush-hosts'

This most likely means your PHP / Java whatever programming language application connecting to MySQL is failing to authenticate with the application created (existing) or that the application is trying too many connections to MySQL in a rate where MySQL server can't serve all the requests.

Some common errors for Too many Connection errors are:
 

  • Networking Problem
  • Server itself could be down
  • Authentication Problems
  • Maximum Connection Errors allowed.

The value of the max_connection_errors system variable determines how many successive interrupted connection requests are permitted to myqsl server.
 

Well anyways if you get the:

Host '' is blocked because of many connection errors; unblock with 'mysqladmin flush-hosts'

You can consider this a sure sign application connections to MySQLis logging a lot of error connections, for some reason.
This error could also appear on very busy websites where high amount of separete connections are used – I've seen the error occur on PHP websites whether mysql_pconnect(); is selected in favour of the prooved working mysql_connect();

The first thing to do before changing / increasing default set of max connection errors is to check how many max connection errors are set within MySQL?

For that connect with MySQL CLI and issue:
 

mysql> SHOW VARIABLES LIKE '%error%';


+——————–+————————————————————-+
| Variable_name      | Value                                                           |
+——————–+————————————————————-+
| error_count        | 0                                                                     |
| log_error          | /var/log/mysql//mysqld.log                                |
| max_connect_errors | 10000                                                      |
| max_error_count    | 64                                                               |
| slave_skip_errors  | OFF                                                             |
+——————–+————————————————————-+


A very useful mysql cli command in debugging max connection errors reached problem is

mysql> SHOW PROCESSLIST;

 

To solve the error, try to tune in /etc/my.cnf, /etc/mysql/my.cnf or wherever my.cnf is located:

[mysqld]
max_connect_errors
variable

and

wait_timeout var. Some reasonable variable size would be:

max_connect_errors = 100000
wait_timeout = 60

If such (anyways) high values is still not high enough you can raise mysql config connection timeout

 

to

max_connect_errors = 100000000

Also if you want to try raise max_connect_errors var without making it permanenty (i.e. remember var setting after MySQL service restart), set it from MySQL cli with:

SET GLOBAL max_connect_errors


If you want to keep the set default max_connection_errors and fix it temporary, you can try to follow the error

Host '' is blocked because of many connection errors; unblock with 'mysqladmin flush-hosts'

suggestion and issue in root console:

mysqladmin flush-hosts

Same could also be done from MySQL Cli with cmd:
 

FLUSH HOSTS;