Archiv der Kategorie: Netzwerk

Website Availability Monitoring

Check, if a website is still reachable – over proxy connection with wget – on windows !!

Wget for Windows ist avalable here.

wget.exe -Y 1 -d -v -S -O D:\Programme\wget\index.shtml -a D:\Programme\wget\

Had to set the environment variable http_proxy=http://proxy.youdomain.somewhere:Port

The used paramters are explained here.



Nexenta Stor: Change default password for webdav user

Just pokin‘ around with the community edition of nexenta store – a fully featured storage appliance based on open solaris. For a full feature list please see more details here.

Currently i’m searching a new NAS to supersede my FreeNAS 7 installation. Unfortunately FreeNAS in it’s current release lacks of some features i liked in V7 – for me the signal to a take a look at Nexenta Stor.

A very handy feature is its possibility to share folders via webdav – BUT: access control is based on a built in user „webdav“ with the standard password „nexenta“.  Making this config available to the internet…. bad idea….

AFAIK there’s no way to change anything acording to webdav-usermanagment neither in the webgui, nor the nms-cli.  Luckily there’s a way to get a real root shell on the nexenta system where you can use good ol‘ htpasswd to change and/or add users to the webdav-authentication:

SSH to your nexenta box:

nmc@nexenta:/$ option expert_mode = 1

nmc@nexenta:/$ !bash

You are about to enter the Unix („raw“) shell and execute low-level Unix command(s). Warning: using low-level Unix commands is not recommended! Execute? Yes

root@nexenta:/volumes# htpasswd  /var/lib/nza/.webdav_passwd webdav

New password:

Re-type new password:

Updating password for user webdav

root@nexenta:/volumes# exit


Important: To re-sync the appliance’s management state information, please

consider running ’setup appliance nms restart‘ command.


Btw: htdigest works as well this way 🙂

W2K8R2: Filecopy over network slow

Problem: File copy on a Windows Server 2008 R2 x64 from a Windows Server 2003 R2 x64 network share is very slow.

Solution (in my environment): Fire the following command as an administrator and reboot the server:

netsh interface tcp set global autotuninglevel=disabled

On a german OS this leads to the following state:


For further reading: Link

Now file copy over network is kind fun again… 🙂

SFlow Extreme Networks

Packet Sampling Basics



Configuring Extreme switches
The following commands configure an Extreme Networks switch (, sampling packets at 1-in-512, polling counters every 30 seconds and sending the sFlow to an analyzer ( over UDP using the default sFlow port (6343):

enable sflow
configure sflow agent
configure sflow collector port 6343
configure sflow sample-rate 512
configure sflow poll-interval 30
enable sflow backoff-threshold
configure sflow backoff-threshold 100
enable sflow ports all

A previous posting discussed the selection of sampling rates. Additional information can be found on the Extreme Networks web site.

See Trying out sFlow for suggestions on getting started with sFlow monitoring and reporting.

Note: Extreme Networks switches support automatic backoff of sampling rates based on a settable samples-per-second threshold. This mechanism ensures that a poorly selected sampling rate will not generate excessive numbers of samples (see sFlow Version 5, section 4.2.2).
Posted by Peter at 9:30 PM

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