IPv6: Test your connectivity on a remote computer via your browser

While test-ipv6.com and ipv6-test.com are great sites for testing IPv6 connectivity on your personal computer, they rely heavily on javascript code in their tests and therefore cannot be used with w3m.

This limitation is quite annoying for testing out IPv6 on your(s) server(s) while enabling IPv6 is at least as important as on any other computer.

Besides ping6, traceroute6 or other basic network tools, there is a way to effectively test IPv6 on a remote computer/server with SSH access enabled. Simply use a socks proxy, by using this command on your personal computer (not the server!):

$ ssh -ND 1080 login@server

-N Do not execute a remote command.
-D Specifies a local “dynamic” application-level port forwarding.

No remote shell session will be open since only traffic forwarding is required here. Now, edit your browser’s proxy settings and activate SOCKS 5 with host localhost port 1080. Go to test-ipv6.com and ipv6-test.com, you should see test results concerning the remote computer/server!

If you are only interested in your IPv4/IPv6 address, lv0.in/ip/ provides this information a clean fashion.

Oh and by the way: <3 IPv6

How to disable random IPv6 addresses on Windows Seven / Vista (no Privacy Extensions anymore!)

There is a lot of information about this « issue » on the web, but the following method is the only one actually effective in my case. This is very useful for setting up DNS AAAA and PTR records for IPv6 auto-configured hosts.

netsh interface ipv6 set privacy state=disabled store=active
netsh interface ipv6 set privacy state=disabled store=persistent
netsh interface ipv6 set global randomizeidentifiers=disabled store=active
netsh interface ipv6 set global randomizeidentifiers=disabled store=persistent

Planned downtime for lv0.in

lv0.in network infrastructure will be down from Tue Nov 23 10:00:00 CET 2010 to an unknown date (maybe after December 15)…

…due to an unscheduled emergency departure from my current apartment to somewhere else in Belfort. Indeed, my roof has turned into moisture because of a water leak and the whole stuff broke down to the floor three days ago…

Sorry for the inconvenience. On the bright side, dresda won’t be affected, including this blog, the wiki, subversion repositories and some other crap.

Stay tuned.

Enabling SNMP on SLM2008 Cisco Small Business Switch

Cisco SLM 2008 is a very efficient layer 2 manageable gigabit ethernet switch, with decent pricing and a large range of features: VLAN, (R)STP, LACP and static link aggregation, 802.1X Authentication, IGMP Snooping, you name it. Even the integrated web interface is quite well designed and not buggy.

But one (native) feature is lacking when you want to monitor per-port network traffic : SNMP.

Here is how to enable and basically configure SNMP on SLM2008 switches.

First, download this script: ename_snmp.pl (Note for Chrome/Safari users: this file may be downloaded as enable_snmp.download, I don’t know why.)

Then there are two ways of using this script :

* remotely by directly altering the switch configuration file.

* locally by first download the switch configuration file, alter it and upload it to the switch.

There is the detail about the remote way, since I used it:

* Configure everything you need in the SLM2008 web interface, especially on the « System » page.

* Open a terminal in the directory where the script was downloaded.

* chmod +x enable_snmp.pl for making the script executable.


$ ./enable_snmp.pl 
Obtaining data from Switch: 
Administrator Username: [ admin ]: 
Administrator Password: [ admin ]: 
Current Body Checksum: 
Current Header Check Byte: 
Both community strings are limited to 15 characters.
New read-only community string: [ public ]: 
New read-write community string: [ private ]: 
New Body Checksum: 
New Header Check Byte: 
End - SNMP Should be enabled.

You will have to provide the right information for , , and parameters.

Finally, use the following command from an host that has network access to the switch:

$ snmpwalk -c   -v 2c

A long output should be displayed, showing every piece of information the embedded SNMP daemon on the SLM2008 can serve.

I hope this will help.


Credits: Cisco support forum and David Holland.