Tuesday, August 2, 2011

OSX and VPN Expiration Issues

After updating to Lion the VPN config began expiring every hour as it was doing in Snow Leopard until I fixed with tips from this site:
http://simon.heimlicher.com/hints/macosx/cisco_vpn-10.6.0-3
From the site, it appears to not apply for Lion, but it does in fact work fine.
By following those directions, your vpn connection to Cisco will stay up for hours :)
regards,
Technical Tips

Tuesday, February 15, 2011

World IPv6 Day: at AppalachianWireless.com

IPv6 is here to stay!

There is plenty of room for growth, new options, and more devices.
And there is a public IP address for everyone.

Due to the ever growing data usage and customers, Appalachian Wireless will be participating in the World IPv6 Day.

This means that when you access www.appalachianwireless.com you will have direct IPv6 or IPv4 access.
If you are on a network that already supports IPv6, than you will connected direct to appalachianwireless.com via IPv6.
If you are still running IPv4, you will be able to continue to access the site via IPv4.

Today, you can already test your IPv6 access by connecting to ipv6.appalachianwireless.com and verifying your network access.

If you are on an ISP who is behind and not able to give you an IPv6 address, there are a number of options available including http://tunnelbroker.net/.

You Always Get More with Appalachian Wireless:



Wednesday, January 19, 2011

ping6 and slow responses

While trouble shooting an IPv6 issue, I discovered that "ping6 <my_ipv6_host>" was getting very delayed responses.

After running tcpdumps and every other debug method I could think of, I finally determined with the help of a friend, that reverse DNS was not setup for <my_ipv6_host>. After fixing this, the ping6 time was like it should have been.

So, do you have a slow ssh or slow ping6 times?
Check for valid reverse DNS.

Wednesday, January 5, 2011

IPv6 and neighbour soliciting

In dealing with a FireWall Router mf-firewall [1] setup and testing, I ran into an issue where my interfaces on my linux box looked like this:

Bonded Interface -> 2 network real network cards
  creating device bond0:
Vlan2
Vlan3
Vlan4
Vlan5

The vlan interfaces where all based on the bond0 device, so all traffic went into the vlan device, than off course exited the bond0 device.

Doing a tcpdump on vlan5 for a workstation located there, I could not see the neighbour requests. Doing the same dump on bond0 I could see it.
Of course the device on vlan5 was not getting the neighbour solicit command.

Finally after some research I was able to fix this with this command:
" echo 1 > /proc/sys/net/ipv6/conf/all/proxy_ndp "

Hopefully this can save someone else some grief.
Perhaps someone else has a better fix.

[1] http://code.google.com/p/mf-firewall/

Thursday, December 30, 2010

MF-Firewall - Linux IPv6 and IPv4 firewall wrapper

A new project, just created yesterday to publish a full software package that uses standard linux tools to create a highly locked down environment.

Basically, a whole suite of scripts written in Ruby that builds chains, sets kernel options, sets up and tears down interfaces and vlans based on a directory of files each part of a zone.

The config directory sits in a folder called /jail
Under that you have acl/ nat/ and mangle/.
Under acl you have zones/ and kernelopts/.
Under zones/ you have each individual zone which includes a special zone called WAN that faces the public. You create as many additional zones as you want. Each zone has its own eth or vlan. A vlan can be TRANS for transparent or it can contact ipv4 or ipv6 address or both.

IPv6 support was only recently added and still needs lots of work done to fine tune it.

Find the project here:
http://code.google.com/p/mf-firewall

Tuesday, December 28, 2010

ssh to IPv6 or IPv4

When typing ssh at the command line, it seems to sometimes do ipv4 and sometimes ipv6.

However if you really want either ipv4 or you want ipv6 you can specify on the command line which you want:

ssh -6 <ipv6 only host>
ssh -4 <ipv4 only host>

Thursday, December 23, 2010

IPv6 and the linux host command...

Working with ipv6/ipv4 and trying to understand how to debug issues...

And more specifically, I wanted to see if DNS was handing both ipv4 and ipv6 addresses.

So, on a mac, typing "host testsystem.example.com", it was returning both A (ipv4) and the AAAA (ipv6) addresses.
But on Debian, only the A address was returned.
Of course ""host -t AAAA testsystem.example.com" returned the AAAA record or the ipv6 address.

So, why did Debian not give me both A and AAAA.
The fix was to install bind9-hosts instead of hosts.

So, if you are running a debian workstation, you might find it helpful to run "sudo apt-get install bind9-host" which will make it replace the hosts package.