And since I am talking about 6to4 in this instance, would 1480 have any benefit over 1280? Or vica versa?
with IPv6 the minimum mtu is 1280. If you are able to increase it (e.g. 1480) your router can decrease the number of fragmented packages, this can give you (slightly) more performance.
If this mtu is really supported, needs to be tested with the "ping6 -s 1472 www.kame.net" command.
But you need to remember that with IPv6 fragmentation is done by the sending host (not by the routers anymore (like in v4)). This means, if there is a connection between you and the target host (on the way to it) which has a smaller mtu than yours, you get a ICMPv6 Type 2 Packet and you have to send your data stream again (with the correct mtu). This can decrease your connection speed. So 1280 might be the right way to go.
Pinging orange.kame.net [2001:200:dff:fff1:216:3eff:feb1:44d7] with 1472 bytes o
f data:
...
Ping statistics for 2001:200:dff:fff1:216:3eff:feb1:44d7:
Packets: Sent = 25, Received = 25, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 235ms, Maximum = 278ms, Average = 241ms
Whereas when I tried the same with MTU 1280 the first packet would time out (probably due to the ICMPv6 Type 2 Packet you mentioned). So it looks like 1480 is good to use now even on kernel 2.4?
root@my.dd-wrt:~# nvram show|grep mtu
pptpd_client_mtu=1450
mtu_enable=0
pptpd_client_srvmtu=1450
ip link set tun6to4 mtu 1480
size: 21098 bytes (11670 left)
wan_mtu=1500
WAN is 1500, set Auto by DD-WRT so does this all jive? I just want to confirm since I don't want to impact my network negatively.
I'm using radvd under dd-wrt.v24-15334_BS_NEWD_std-nokaid.bin using the radvd 6to4 k2.4 config from the wiki but with 1480 instead of 1280 for the MTU, same goes for the startup script.
Hmm I just did some ping -6 tests with ipv6.google.com and oddly only those with packet size under 1432 made it through, all higher ones got Destination net unreachable.
It's no 1480 or 1472 even, but that and the nvram info I pasted above looks pretty compelling for my case that k2.4 supports higher MTUs than 1280 though.
Edit: Tested with google again with config+script MTUs set to 1280, and 1232 is the highest packet size before Destination net unreachable. Not sure what the extra 48 bytes go to but there we are, definite pattern.
Last edited by on Thu Oct 07, 2010 3:56; edited 2 times in total
Joined: 09 Apr 2009 Posts: 159 Location: Rochester NY
Posted: Thu Oct 07, 2010 3:46 Post subject:
Ok, I must be missing something somewhere because it isn't working. I have a tunnel through HE, but I'm not sure I have all the parameters corrected from the examaple in the first post. I'm slightly confused since it is alegedly a functioning script for sixxs. Can someone please post a functioning example for HE? Thanks. _________________ -mpyusko
Joined: 09 Apr 2009 Posts: 159 Location: Rochester NY
Posted: Thu Oct 07, 2010 13:56 Post subject:
Thank you. I went through the script and set it up as best I can, but for some reason my JFFS says 64k, 0k available therefore it it empty. Not sure why.
Edit: I just upgraded to DD-WRT v24-sp2 (09/18/10) std-nokaid
(SVN revision 15230M NEWD Eko) And enabled ipv6, jffs2, etc.
root@river:/jffs# df -h
Filesystem Size Used Available Use% Mounted on
/dev/root 2.8M 2.8M 0 100% /
/dev/mtdblock/4 128.0K 128.0K 0 100% /jffs
insmod ipv6
sleep 5
WANIP=$(ip -4 addr show dev vlan1 | awk '/inet / {print $2}' | cut -d/ -f1)
MY_TUNNEL_ADDR="2001:470:xxxx:xxx::2" # change me
MY_ROUTED_ADDR="2001:470:xxxx:xxx::1" # change me
echo "External IP:" $WANIP > /jffs/startup.debug
if [ -n $WANIP ]
then
echo "configuring tunnel" >> /jffs/startup.debug
# The following commands are straight from HE's website
ip tunnel add he-ipv6 mode sit remote 216.218.224.42 local $WANIP ttl 255
ip link set he-ipv6 up
ip addr add $MY_TUNNEL_ADDR/64 dev he-ipv6
ip route add ::/0 dev he-ipv6
# These commands aren't on HE's website, but they're necessary for the tunnel to work
ip -6 addr add $MY_ROUTED_ADDR/64 dev he-ipv6
ip -6 addr add $MY_ROUTED_ADDR/64 dev br0
ip route add 2000::/3 dev he-ipv6
echo "starting radvd" >> /jffs/startup.debug
radvd -C /jffs/radvd.conf &
fi
I can't seem to create files on /jffs. I think that is my only issue. (???) _________________ -mpyusko
Joined: 09 Apr 2009 Posts: 159 Location: Rochester NY
Posted: Thu Oct 07, 2010 21:48 Post subject:
As far as I can tell it seems to be assigning IPv6 addresses throughout my network, but http://whatismyv6.com/ doesn't seem to detect I have a IPv6 address. What am I missing? (oh, the wifi connection on my Linux laptop is being properly assigned, but when I switch to wired, it's the OS default address... I think). _________________ -mpyusko
When you put your radvd config into the webgui (on administration tab) it is available at /tmp/radvd.conf. You can use this instead of creating a /jffs/radvd.conf file (I have issues with my jffs on my WRT350N). I have my startup.debug file in /tmp/startup.debug as well. ~methaneb
Seems like your issue. Modify your script accordingly and you should be fine Basically just go back and disable jffs and then change all instances of jffs in the script to tmp. Remember to read everything - there's lots but it's often handy hehe.
Joined: 09 Apr 2009 Posts: 159 Location: Rochester NY
Posted: Fri Oct 08, 2010 2:16 Post subject:
I'm sorry, I should've posted that I already tried changing all the jffs to tmp. I'm not sure what the problem is. My Wired adapter seems to be addressed properly for IPv6, but still, it is not testing ok remotely.
In the HE section of the wiki it states to use a radvd script. there are a couple shown elsewhere in the wiki, but not under the HE section.
Also, the starup.debug shows radvd starting, but when I ssh into the router it is not loaded and I have to start it manually.
Another symptom, when radvd is not running, my wired nic in the laptop is addressed properly but the whatismyv6.com test is quick to say only v4 is running. Once I start radvd, the test takes a few minutes before it determines only v4 is running. _________________ -mpyusko
If you're using that interface br0 chunk of code from the top of the wiki under the radvd config section in the webgui then I think you're using it the right way.. Though it does look a little empty to me - You could also try the one from the 1st post of this thread to see if it helps.. Or try that script and method in its entirety making sure you fill in all the variables (BLAH=stuff) from the beginning and change what it tells you to in the radvd as well.
If all that doesn't work then I'm really not sure what's going on with your setup.. Not really my area of expertise either as I've only set up local 6to4 on a couple routers so far.. So I'll bow out to someone elses knowledge in the thread here and hopefully they can help you.
Joined: 09 Apr 2009 Posts: 159 Location: Rochester NY
Posted: Fri Oct 08, 2010 15:47 Post subject:
I tried using the original script from the first post, but couldn't make sense of it for an HE setup, so I was directed to the wiki.
I'm using opendns, and when I try to go to places like ipv6.whatismyv6.com it comes back as unresolved or not loading.
Code:
ping6 ipv6.google.com
PING ipv6.google.com(iad04s01-in-x68.1e100.net) 56 data bytes
From mpyusko-1-pt.tunnel.tserv9.chi1.ipv6.he.net icmp_seq=1 Destination unreachable: Address unreachable
Code:
(On my Debian Laptop)
#
# radvd configuration generated by radvdump 1.1
# based on Router Advertisement from fe80::223:69ff:fe5b:a0d2
# received by interface eth0
#
Will these packages work on an ASUS RT-N16?? _________________ ASUS RT-AC68U [Kong build 24850] = main router
Linksys E2000 [Build 15962M NEWD-2 K2.6 big] = client bridge
If you're signature is correct then you're using a 2.6 kernel. What you're trying to install is iptables modules for kernel 2.4.34. That won't work. Don't know the build you're using so I can't recommend a package. Maybe someone else can help?
And the '-d ' switch you're trying to use -> ipkg help output:
Quote:
-d <dest_name> Use <dest_name> as the the root directory for
-dest <dest_name> package installation, removal, upgrading.
<dest_name> should be a defined dest name from the
configuration file, (but can also be a directory
name in a pinch).
So, using a destination folder of '/' or '/jffs' would make sense. I my case the correct destination root is already defined in /etc/ipkg.conf and I didn't have to specify that option. I think you shouldn't have to pass that option either.
Posted: Tue Oct 12, 2010 17:19 Post subject: solved! (i think...)
I am on a 610n v2, using BS build 15407 mega (Now 15441 Mega)
so for the longest time I could get the router to ping6 a site (google, kame) no problem. radvd was assigning a ipv6 address to my pc (xp) but ping6 would time out. Finally found this thread:
and now I can see the dancing turtle, and get to ipv6.google.com, but interestingly whatsmyipv6.com says I am IPV4 (and ping6 says bad address!)
not the cleanest but,heres my code:
=======================================
insmod ipv6
sleep 5
WANIP="67.174.xxx.xxx"
MY_TUNNEL_ADDR="2001:470:1f10:xxx::2" # change me
MY_ROUTED_ADDR="2001:470:1f11:xxx::1" # change me
echo "External IP:" $WANIP > /tmp/startup.debug
if [ -n $WANIP ]
then
echo "configuring tunnel" >> /tmp/startup.debug
# The following commands are straight from HE's website
modprobe ipv6
ip tunnel add he-ipv6 mode sit remote 209.51.181.2 local 67.174.xxx.xxx ttl 255
ip link set he-ipv6 up
ip addr add 2001:470:1f10:xxx::2/64 dev he-ipv6
ip route add ::/0 dev he-ipv6
ip -f inet6 addr
# These commands aren't on HE's website, but they're necessary for the tunnel to work
ip -6 addr add $MY_ROUTED_ADDR/64 dev br0
ip route add 2000::/3 dev he-ipv6