Category Archives: Hardware

Time for a new Mac?

I really love my Macs. Well, mostly. But lately, it’s more like a love-hate relationship. My Macbook will only wake up from sleep on the second or third keystroke. While I’m typing, it sometimes freezes for a while and when it comes back, it will echo the first character I typed before it went into “lala-mode” for eternity (makes editing scripts in

vi

real fun, btw.).
And then, there’s the Macbook Pro.

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Nachgelötet

t4_kombiinstrument_steckverbindung_loetseiteHeute hatte ich endlich mal Zeit, ein schon länger anstehendes Projekt durchzuziehen: Das Nachlöten der Steckkontakte im Tacho meines VW-Bus T4. Weil zufällig bin ich im T4-Wiki darüber gestolpert, dass kalte Lötstellen die Ursache für die ständige blinkende Kühlwasser-Kontrolleuchte sein könnten. Das Ergebnis:

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Notebook-Kuschel-Beilage

Für Relax-Worker: Das CushTop von Belkin

Für Relax-Worker: Das CushTop von Belkin

Manchmal sind es ja die einfachen Dinge, die am meisten Spaß machen. Eigentlich hätte ich ja nicht gedacht, dass das Cush Top wirklich was bringt. Aber in meiner bevorzugten Arbeitsposition (liegend, Füße auf dem Tisch) ist es doch angenehmer, als das Notebook immer als Oberschenkelwärmer zu benutzen.

Big brother

Following up my experience with Mr. DREAM, first thing to say is that it only stayed 2,5 days at my house due to a weekend being between delivery and return.

The DM600 is a neat small machine but didn’t meet my expectations for a couple of reasons.

Most of all the picture quality was bad. Even for DVB-T it was absolutely inacceptable. Furthermore it neither found the NAS to store nor did it write to the internal (2,5 IDE) HD. I guess that a FW-Upgrade could have solved most of these issues but this directly brings me to the next stage. Updates only can be performed via null modem cable with the box detached from the TV. Not the way I want to handle any of my networking equipment.

And finally I underestimated the importance of a second tuner. Being unable to zap between channels while recording was the definite killer for the DM600.

In the meanwhile I did what apparently I always have to do …. I went for the big brother and payed way more than my budget had been approved for. Today the DREAM 7025 is feeding my TV and I just love it!

The thing has 2 tuners which you can easily daisy chain. Zapping and recording is no problem at all now and flashing a new FW can easily be done via the network. EPG works fine and once you’re accommodated to the GUI, you’ll very soon like it a lot. On top come all the neat Linux extensions that you can easily install from the internet via network. I’m not sure how important e.g. the Adelaide webcam will become for me but knowing it’s there is a good feeling.

The feature I love the most is the network compatibility and the web interface. Sure there’re several additional add-ons within the community but even the standard tool is grand. Stefan here would certainly find various ways to remotely access and tweak the box, I for myself enjoy sitting on the balcony or anywhere in my home and watch TV (in great quality) on my Laptop over WLAN.

NcFTP 3.2.1 for ReadyNAS

Today I finally got fed up enough with the crippled and outdated version of NcFTP shipped with the ReadyNAS that I compiled my own version. The result is ncftp-3.2.1-ReadyNas.tar.gz.

Installation ist quite easy:

  1. If you haven’t done already, install the ReadyNAS extensions ToggleSSH and EnableRootSSH
  2. Copy the file to your ReadyNAS, preferrably to the /root directory using scp.
  3. Log on to the shell of your ReadyNAS using ssh as user “root”.
  4. Change to the / directory, eg “cd /”.
  5. Unpack the archive using “tar xzf /path/to/ncftp-3.2.1-ReadyNas.tar.gz”
  6. Enjoy

All files will be unpacked to /usr/local, not overwriting any existing copies of the ncftp tools previously installed. To use the new version you may have to log out and log in again.
As always: Works for me, ymmv. If using this software breaks your ReadyNAS you own the parts.

iPhone: Admin’s Best Friend?

So there I was, playing with the currently “most wanted mobile phone on earth”. Game over now, the iPhone is back with Apple. Now, what did I take from playing with it? First, it’s addictive as hell. Totally. Once you’ve got your hands on it for more than five minutes, you really so want one. Second, without a good service plan, it’s only half the fun. With Internet access being so easy you’ll want to use it. Anytime, anywhere. Third, it’s not fit for hardcore admin use – yet. That’s because it lacks two features I absolutely need: Skype and an SSH terminal. Both of which may show up in time now that the SDK is available. Still, it makes me wonder that Apple built VPN capabilities into the phone but didn’t offer an SSH terminal. Sure, you could install one by jailbreaking the iPhone but I didn’t want to do that to an eval unit. This hurts even more since I found out that I could really use the onscreen keyboard – something I wasn’t really sure about before testing the iPhone.
So, for now it’s still the BlackBerry for me. But maybe, I will have another look in 60 days. If I weren’t an admin, I’d run not walk to get an iPhone.

iSCSI Target Support for ReadyNAS updated


UPDATE: Instead of writing ever new blog posts, an always up-to-date page for the iSCSI Target Support for ReadyNAS is now available.


Since the iSCSI project has released a new stable version I felt it was time to upgrade the iSCSI Kernel Modules and Utilities for ReadyNAS. Klicking on the link will give you version 0.4.16 which contains the following changes:

{openx:6}

  • fix overzealous assert() in digest_data()
  • add checking on return value of ISCSI_PARAM_GET
  • 2.6.22, 2.6.23 and 2.6.24 compile fixes
  • add conn->rwsize check
  • avoid potential NULL-ptr dereferences in rx and tx buffer
  • fix the shell syntax in init scripts
  • fix digest endieness on LE archs
  • fix SPARC alignement issues
  • fix DISTDIR in Makefile for /etc install
  • add support to nullio for volumes > 2TB
  • remove init.d memory size adjustment
  • add error code reporting to blockio_open_path
  • blockio gen_scsiid bug fix
  • add verbosity to kernel output and task management

Installation is the same as described here with one exception: The supplied configuration example is now named /etc/ietd.conf.sample, so installing the version won’t overwrite an existing configuration file. On a fresh install you’ll have to rename the example configuration to /etc/ietd.conf before you can actually use the iSCSI target support.

Tuning the Sun: Fiddling with the TCP/IP stack

Well, it’s over one and a half years that I first posted some hints about tuning the performance of a Sun web server. Now it seems that I found what looks like the optimum settings for the machines I’m currently watching over:

tcp_conn_req_max_q               1024
tcp_conn_req_max_q0              10240
tcp_rexmit_interval_min          2000
tcp_ip_abort_interval            600000
tcp_ip_abort_cinterval           60000
tcp_keepalive_interval           3600000
tcp_time_wait_interval           30000
tcp_fin_wait_2_flush_interval    67500
tcp_smallest_anon_port           8192 

That’s mostly consistent with what Jens S. Vöckler writes on his site, just a bit more condensed.

ReadyNAS goes iSCSI


UPDATE: Instead of writing ever new blog posts, an always up-to-date page for the iSCSI Target Support for ReadyNAS is now available.


iSCSI target on the ReadyNAS

As much as I like the ReadyNAS, there’s one feature I’ve been missing since day one: Being able to define an iSCSI target. Well, since the code is out there, I set about to make it work on the ReadyNAS. Luckily, there’s now some sort of development kit available, and for I had a spare ReadyNAS unit to break, there was nothing to stop me. To cut a long story (with many gory details) short: Mission accomplished.

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Speed up your bonds

Uh. Well. Not really ;) But in case you’re using bonded network interfaces with Linux you may have noticed that they’ll always report a network speed of 10Mbps – no matter what NICs you used to create the bond. Technically this isn’t a real problem for the bond will always work at the full speed supported by the hardware. But it can pose a management problem when you’re using SNMP to monitor your devices.That’s because a common monitoring technique is to set limits after reaching which the system will send off an alert. And it’s easy to imagine that an assumed 10Mbps link will reach a saturation point of, say, 75 percent a lot earlier than, say, the 1Gbps interfaces you’re actually using to create to bond.

{openx:6}

Now for the bad news: There’s nothing you can do locally to change the speed reported by the bond (or, to be fair, by the various tools used to determine the link speed of any given interface). The good news is that you can do something to have at least your SNMP daemon report the correct link speed. As long as you’re using net-snmp, that is.The first step is to determine the index number of your bond interface(s). This can be easily done using

snmpwalk -v 2c -c <community> -Os 192.168.0.1 interfaces | more 

Just replace <community> with the name of your SNMP community (in general, “public” is a good guess) and the 192.168.0.1 with the IP address of the system you’re monitoring. You should get something like this:

ifDescr.1 = STRING: lo
ifDescr.2 = STRING: eth0
ifDescr.3 = STRING: eth1
ifDescr.4 = STRING: eth2
ifDescr.5 = STRING: eth3
ifDescr.6 = STRING: eth4
ifDescr.7 = STRING: eth5
ifDescr.8 = STRING: bond0
ifDescr.9 = STRING: sit0 

As you can see, in this example our bond interface is located at ifDescr.8. Write down the number or try to remember it for a few seconds. Now, on the machine where the bond is running, open the file /etc/snmp/snmpd.conf. Somewhere in that file, insert

override ifSpeed.X uinteger 1000000000 

{openx:6}

Don’t forget to replace the X with the actual number from the snmpwalk output. And make sure not to type ifDescr but ifSpeed instead. This is telling your SNMP daemon to overwrite the netlink speed as reported by the operating system for interface X with 1.000.000.000 – which translates to 1Gbps.

Now all that’s left to do is to restart your SNMP daemon – and possibly to rebuild the device data for this server in your management application. Ah, and there’s one drawback: In case you ever change the bond or add or remove a NIC to/from that server, the order of the interfaces and thus their numbering will change. So you’ll then have to repeat the steps outlined above.

And one final note: In theory, you should be able to achieve the same result using the line “interface bond* 6 1000000000” in your snmpd.conf. This would have the benefit of always changing the value for all interfaces named bond… — however, I couldn’t make this work on any machine I’ve been experimenting with. Ymmv.

Nice ReadyNAS Widget

Just stumbled over this little gem which in fact is a bit older already:

Gives a nice overview of the ReadyNAS‘s health for Mac users. Sorry for the Windows world though: still no widget for you.

ReadyNAS NV+: Here Today, Gone Tomorrow

ReadyNAS NV+ And ReadyNAS NV
Today I received the ReadyNAS NV+ so that I could compare it to my trusty ReadyNAS NV. Except for the LC display on the front, there has nothing changed in terms of connectors or buttons. Also from a first glance, there’s no change to either the firmware nor the internals. As some tests revealed even the performance of both devices is almost equal with a slight advantage for my older ReadsNAS NV. But since that’s just a second for transferring one Gigabyte worth of data, I guess that’s well within tolerances.

ReadyNAS NV Frontpage

ReadyNAS NV+ Frontpage

What I found interesting is that my old ReadyNAS NV is equipped with faster RAM than the new ReadyNAS NV+. However, as the tests showed this doesn’t make a difference in any way. So, basically, there’s no need for me to upgrade but if you haven’t bought a ReadyNAS NV+ yet, I can safely say that the product is as fast and as reliable as the older one. And as much as I’d like to keep it, it’ll be repacked and ready to be on it’s way back to Netgear by this time tomorrow.

Easy Come, Easy Go

It wasn't meant to be
Today I received a parcel from Netgear. After unpacking I was astonished to not find the product I was expecting but an EVA 8000 instead. Being a nice guy I called Netgear and asked whether it was really meant for me and found that unfortunately it wasn’t. Since there was someone desperately waiting for it I repacked the stuff and sent it off again. Maybe another time, then.

Business Toys

Cruzer EnterpriseCruzer Professional
Last week SanDisk sent two little toys to play with: Their new USB memory sticks Cruzer Professional and Cruzer Enterprise from their business line of that product category. Now, what’s that? USB memory sticks for businesses sound a bit strange at first, but wait for the specs. Both are available in sizes of 1, 2 and 4 GB (and of course I only got the 1 gig version) to store valuable business data. Now, why would one want to do that? That’s where the “business features” kick in:
Both sticks sport an AES 256 encryption chip to protect the data on them. While this is done automatically for the whole drive on the Enterprise version on the Cruzer Professional the user can choose how much of the space will be encrypted. Since the crypto stuff is done in silicon, the sticks are pretty fast when reading and writing data. To access the encrypted stuff you have to start a Windows application stored on the sticks. This renders the Cruzer Enterprise pretty useless for me.
In an Enterprise environment where Windows prevails this is not a real problem. And there, you might want to check out the additional SanDisk Central Management and Control Software. Requirements to run the software are pretty steep: Windows 2003 Server, Active Directory and SQL Server 2000 at a minimum. In a matching setup you can automatically provision the sticks, create device-user associations, backup the contents of the sticks and – most importantly – lock the stick or even make it format itself after a loss or theft. Well, that’s at least what the docs tell me. I’ll see whether I get around to testing these promises. For now, I’m just using the Cruzer Professional to swap some data between my Mac and Linux boxes around here ;)

Netgear liefert ReadyNAS aus

Netgear ReadyNAS NV+
Ich zitiere mich ja eigentlich nur ungern selbst aber in dem Fall mache ich mal eine Ausnahme:

Netgear liefert ab sofort seine neue ReadyNAS Storage-Produktfamilie von Desktop- und Rackmount-fähigen Speicherlösungen mit vier SATA-Festplatteneinschüben aus. Die elegante Desktop-Variante für anspruchsvolle Heim- und professionelle Anwender ist in drei Konfigurationen erhältlich: jeweils 1 TB Speicherplatz bieten die Modelle RND4250 mit 2 x 500 GB SATA- und RND4425 mit 4 x 250 GB SATA-Festplatten. Die unverbindliche Preisempfehlung für beide Varianten liegt bei jeweils 1.200,- Euro inklusive Mehrwertsteuer. Die größte Desktop-Version RND4450 verfügt über insgesamt 2 TB, verteilt auf vier 500 GB SATA-Festplatten (1.900,- Euro UVP).

Ich hab’ das Ding ja damals noch direkt von Infrant bekommen und finde es nach wie vor Klasse. Weniger Klasse ist der offizielle Preis, aber wie Volker schon schreibt gibt es die 1-TB-Version bei Cyberport schon ab 899 Euro. Da kann man zwar immer noch meckern, aber nicht mehr ganz so viel ;)

What a difference a Switch makes

No, I’m not talking about converting to the Mac here, although I did that, too, some years ago. Instead I yesterday received a replacement for my network’s main switch, a trusty but somewhat outdated Netgear GS524T. The new heart of my wired network again comes from Netgear, a GS716T.

Netgear GS716T

Sporting eight ports less than its predecessor it comes with a feature I deperately needed: the switch can be managed using a web browser or – if need be – a Windows application. This feature was very instrumental in detecting a bad network interface on my LAN that caused a lot of trouble. Instant other benefit: the support for jumbo frames allows me to get data to and from my NAS faster.
In addition, the GS716T allows for port trunking, so I guess my servers will be connected using really fat pipes in the near future. I’m not so sure whether I’m going to use the VLAN feature, though. Only drawback: the switch is actively cooled by two very small and thus very noisy fans. So you better put it in an enclosure which is what I did.

Reset BIOS Password for an Acer T250

If you ever forget the BIOS password of an Acer T250 notebook here’s a method to reset it: Open the notebook and look for the DIP switch located below the keyboard. Set switch number 1 to the “On” position. Power on your notebook. Power off again. Reset switch 1 to it’s original position. Re-assemble the notbook. Store spare parts in a safe place. Done. Might also work for other Acer notebooks but no guarantee given.