20/09/2016

Dell Latitude E7470

Finally I changed my working laptop, 8 years ago I switched from an old IBM ThinkPad R50 (yes! It was a true IBM ThinkPad!) to a T500 ThinkPad from Lenovo.

It was a good pc, not very powerful but sturdy, with a full size keyboard and so many options for upgrade like any other ThinkPad, a war machine!
Now the glorious T500 needs to retire, everything works but I need an SSD, the screen resolution was ridiculous, CPU and RAM were inadequate to run any virtual machine in local, so I started to look around for a new pc, these were the requirements:

  • CPU at least Core i5
    I don’t need a huge computing power beacause I don’t have to render or compile source (I usually spend most of my working time in an ssh shell) and I don’t want a Boeing 747 fan on my side and a heavy PSU.
  • RAM at least 8GB
  • SSD storage (I think I don’t have to explain why…)
  • Display resolution at least 1920×1080 (I don’t want to go crazy with external display for work)
  • 14″ chassis (I hate those horrible 15,6″ chassis with the imho useless numbers keypad)
  • Business line laptop

I started looking for a laptop with these requirements and I came to the Dell Latitude 5000 series, nice line, solid, realiable and with a great customer care (this is my experience with any Dell product, pc or server).
Sadly I had a bad experience with a Dell partner so I started to looking around for an alternative… but last week one of our historic wholesale providers started to sell Dell products and I found the shiny Latitude E7470 which fits perfectly into my requirements to an honest price… check, check, check!

spacey

So, here it is my brand new laptop, my first experience with a Latitude product.

My first impressions:

  • it’s thin and light (it’s branded as ultrabook although I don’t think it fits the Intel requirements for that) but it’s super sturdy!
  • the display is AWSOME! It fully deserves all the good feedbacks you can find online.
  • great I/O and options, It has 3 USB 3.0 ports (not bad for a thin laptop), two display output (mini DP and HDMI), it has uSIM slot and also an integrated smartcard reader.
  • nice storage performance (more than 500 MBps in sequential read and more than 250 MBps in sequential write) and I read It’s possible to install a second SSD on another slot.

The only complaint I had is about some keys (for example HOME and END keys which I use a lot) that need the FN key, and obviously the stupid Windows 10 scaling which blurs everything (but this is not a Dell problem).

And yes… I have to use Windows for now… :\

Here is the beast

e7470_1 e7470_2

02/07/2016

Psi Probe error

If you work with j2ee application you need Tomcat and not some stupid gigantic enterprise application server, and if you work with Tomcat you really need Psi Probe because it’s the best Tomcat manager you can find all over the galaxy.

Recently I noticed a strange behavior from this tool after some activities focused on security hardening.
I had some old Tomcat 6 instances where I want to get rid of Tomcat version inside error pages and inside http headers, after I removed these data Psi Probe went crazy with a nasty exception “java.lang.RuntimeException: No container found for your server” :\

error

After some googling I found that Psi Probe uses ServerInfo to determine the Tomcat version, I completely erased this information for security issues so the poor Psi Probe lost its mind…

The solution is quite simple, open the probe.war archive (you can unzip it) and change the WEB-INF/spring-probe-resources.xml file this way:

  1. find “forceFirstAdaptor” variable inside the “com.googlecode.psiprobe.beans.ContainerWrapperBean” and change it’s value from false to true
  2. change the list inside the “adaptorClasses” property putting as first record the value referring to your Tomcat version (in my case “<value>com.googlecode.psiprobe.Tomcat60ContainerAdaptor</value>”)

spring-probe-resources

After that you only have to repackage the files and deploy the war.

17/06/2016

nmon-script

Nmon is wonderful, if you need to monitor you server resources in realtime it’s your tool, if you need to monitor resources statistics over time and save them it’s your tool, if you need to check what’s the status of your server’s resources in a precise moment it’s your tool.
I can’t imagine a scenario where you don’t need nmon, more useful and flexible than sar, simpler and more straightforward than any other web based tool, imho it’s the perfect companion for collectd.

Sadly during on my last server setup I noticed that the latest nmon package distributed by Epel repository lacks of all the cron scripts you need to automate nmon startup and data collection, which imho are very useful also if you get nmon directly from the official GNU/Linux project site.

Here’s some hints from the old packages, first of all create the /var/log/nmon directory with nobody user as owner.

nmon01

Create a new script in cron for example /etc/cron.d/nmon-script.
This cron will launch /usr/bin/nmon-script every day (for example at midnight).

nmon02

Now you have to create the /usr/bin/nmon-script file (remember to give execution permission) which has:

  • some configuration parameters in /etc/sysconfig/nmon-script
  • commands to kill, cleanup old files (disabled in the example, note the leading # at line 15)

nmon03

Create the /etc/sysconfig/nmon-script which contains some useful varibles (the directory where to save nmon archive files, retention and nmon options).

nmon04

That’s enough, at the next midnight nmon will start to save your resources statistics in /var/log/nmon/<hostname>_AAMMDD_0000.nmon files.

nmon05

You can download all the scripts and files to quickly setup the nmon-script:
nmon-script.tar.gz (656B)
SHA256 hash: 953667d8e2806e4858426fb000d7f3cfc898c53e26ffc7694bf2722442668aa8

[EDIT]

Nmon is not distributed by Epel but from RPMForge!!
Although RPMForge version is quite old it has nmon-script cron, I suggest to move to the latest version from the official GNU/Linux project site which do not have nmon-script.

30/04/2016

SSD galore!

I don’t know why, but I always had a bad feeling about Samsung products, every time I bought or tried one of them I always had  so many problems…

In december 2014 I gave to my brother a brand new Samsung 840 Evo SSD for his old MacBook Pro.
The original MacBook Pro hard drive was a crap, 5400rpm and really really slow, with this SSD it would take off like a rocket!

Everything was ok (except the stupid Apple policy regarding trim on ssd…) until the last february when the system became unstable, after some check I found the problem was the SSD.
I went back to the shop to start an RMA procedure, and finally yesterday (after almost two months!) they sent me a brand new 850 Evo with 3D V-NAND.

Let’s see how it works compared to my good old Crucial M4 (which is 4 years and 3 months old!).

This is the Crucial M4, keep in mind that on this SSD I run the OS (Windows 10 Pro) my software and games (Far Cry 4 and Eve Online atm),  I did nothing to preserve it’s lifetime and performance and it’s 75% full.

CrystalDisk_CrucialM4

as-ssd-bench M4-CT128M4SSD2 29.04.2016 22.29.11

This is the new Samsung 850 Evo with 3D V-NAND (clean and absolutely empty).

CrystalDisk_850EVO as-ssd-bench Samsung SSD 850 29.04.2016 22.20.38

The difference on write test is HUGE, access time is also impressive!
To be honest I did not expect these results from my old Crucial M4, it runs very well also after so many years and so many writings on his back, excellent product!

Let’s see if this new SSD will defeat my Samsung curse! ;)

22/04/2016

Time to upgrade

I can’t tolerate these Out Of Memory errors from the latest Call of Duty!
I can’t tolerate the thrashing each time I test something heavy on vmware!

Time to do some upgrade ad switch to 16 gigs of shiny new Corsair RAM for my gaming/testing platform!

ram1

ram2

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