re: harvesting energy
If we're talking about kids powering their own devices, I think the way to go is to turn work into play. The merry go round/hard bar swing would fit in this category. So basically, let's look at activities where energy exerted is ambient anyway? What I mean is that the energy is being used up by the kids anyway, so why not tap into those. An example is to give them some variant of those dance straps meant to power cellphones before they go off to run and play during recess and lunch break. One way to tap into this would be to create new playground installation toys which can be used for harvesting energy. Q: how much abuse can a kinetic energy harvester withstand? A soccer of basketball has a lot of kinetic and impact energy bouncing around. I'd imagine that's too much abuse though, and whatever harvesting mechanism would break from the forces. Would piezo work there? I think I remember a concept where a dance floor would have piezo harvesters and when people dance on the tiles, they light up? Another problem is battery... how efficient and how much can a battery really store from these small bursts of energy? Sorry guys, I can't do math anymore since I got traumatized in college, so would appreciate it if these were translated into equation-less layman's terms. (btw, really appreciate the PDF human-powered energy harvesting! It was a really nice surprise that some of the solutions I'd been thinking off for years were in there :) ) -Naz -- carlos nazareno http://twitter.com/object404 http://www.object404.com -- core team member phlashers: philippine flash actionscripters http://www.phlashers.com -- poverty is violence ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
10.1.3 image and Firmware q2e42
Hi! We are using a software image based on dextrose, I know that the official OLPC software image is different, but for this question I think that is the same. We want to install dextrose (suppose 10.1.3 image) with the firmware q2e42. What do you think? This is possible or we will have problems with this combination of firmware and software image? Regards, Daniel. -- Forwarded message -- From: Daniel Castelo dcast...@plan.ceibal.edu.uy Date: Tue, Feb 1, 2011 at 4:25 PM Subject: Dextrose and Firmware q2e42 To: dextr...@lists.sugarlabs.org We have delivered dextrose 1.0 for our XO 1.5 machines, we want to release this version to XO 1.0 one's, but based on some bad experiences that we had in the past we aren't allowed to update the firmware (problems with some machines that remained broken after the process). The question is, if we have the firmware q2e42 installed, will dextrose (version 1) run properly in this machines? After a first test ( ten minutes one) seem that works, but I suppose that we could have some problems if we don't update the firmware to the last version. Thanks Daniel -- Ing. Daniel Castelo Plan Ceibal - Área Técnica Avda. Italia 6201 Montevideo - Uruguay. Tel.: 2 601 57 73 Interno 2228 E-mail : dcast...@plan.ceibal.edu.uy -- Ing. Daniel Castelo Plan Ceibal - Área Técnica Avda. Italia 6201 Montevideo - Uruguay. Tel.: 2 601 57 73 Interno 2228 E-mail : dcast...@plan.ceibal.edu.uy ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: 10.1.3 image and Firmware q2e42
daniel wrote: Hi! We are using a software image based on dextrose, I know that the official OLPC software image is different, but for this question I think that is the same. We want to install dextrose (suppose 10.1.3 image) with the firmware q2e42. What do you think? This is possible or we will have problems with this combination of firmware and software image? you can read the release notes for the firmware releases between q2e42 and q2e45 here: http://wiki.laptop.org/go/OLPC_Firmware_q2e45 http://wiki.laptop.org/go/OLPC_Firmware_q2e44 http://wiki.laptop.org/go/OLPC_Firmware_q2e43 i'm sure the release will run. but q2e45 in particular contains a fix for machines hanging during boot (d.l.o #9100) as well as EC firmware which fixes issues with resuming from suspend from the touchpad. you can also see that q2e43 fixed very many bugs -- many of them are related to the selftest diagnostics, but others could affect OFW's ability to install new releases. we don't issue new firmware lightly, and of course we recommend that deployments always use the latest firmware. paul Regards, Daniel. -- Forwarded message -- From: Daniel Castelo dcast...@plan.ceibal.edu.uy Date: Tue, Feb 1, 2011 at 4:25 PM Subject: Dextrose and Firmware q2e42 To: dextr...@lists.sugarlabs.org We have delivered dextrose 1.0 for our XO 1.5 machines, we want to release this version to XO 1.0 one's, but based on some bad experiences that we had in the past we aren't allowed to update the firmware (problems with some machines that remained broken after the process). The question is, if we have the firmware q2e42 installed, will dextrose (version 1) run properly in this machines? After a first test ( ten minutes one) seem that works, but I suppose that we could have some problems if we don't update the firmware to the last version. Thanks Daniel -- Ing. Daniel Castelo Plan Ceibal - Área Técnica Avda. Italia 6201 Montevideo - Uruguay. Tel.: 2 601 57 73 Interno 2228 E-mail : dcast...@plan.ceibal.edu.uy part 2 text/plain 129 ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel =- paul fox, p...@laptop.org ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: [Server-devel] Hidden SSID and Proxy settings
On Mon, Jan 31, 2011 at 1:15 PM, Dr. Gerald Ardito gerald.ard...@gmail.com wrote: I am trying to connect XOs in a school which as a wireless network with a hidden SSID. Additionally, the school requires proxy settings to establish internet connections. Can someone help me with this? Very tricky. The Sugar side won't wandle this situation very well at all. GNOME can handle it. Under Sugar - You may be able to set the proxy setting with a pac file. Pia Waugh reported once that it worked with 8.2.1, but I don't think she documented it. - Hidden SSIDs are not handled well at all by Sugar's network neighbourhood. cheers, m -- martin.langh...@gmail.com mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: [Server-devel] Hidden SSID and Proxy settings
On Mon, Jan 31, 2011 at 2:15 PM, Dr. Gerald Ardito gerald.ard...@gmail.comwrote: I am trying to connect XOs in a school which as a wireless network with a hidden SSID. Additionally, the school requires proxy settings to establish internet connections. Can someone help me with this? Thanks. Gerald This wouldn't happen to be in NYC, would it? I remember reading a long time ago that the schools there have a policy that SSIDs can't be broadcast. You might deter my Grandma with that, but it's almost pointless as a security measure. http://olpcnyc.wordpress.com/2008/05/09/connecting-to-hidden-wifi-networks/ That workaround is likely deprecated now, though. Anna Schoolfield Birmingham ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: [support-gang] [Server-devel] Hidden SSID and Proxy settings
2011/2/1 Dr. Gerald Ardito gerald.ard...@gmail.com Thanks, all, for the support. I'll let you know how it goes. I am also working to set up a schoolserver in this school, to ultimately mitigate this problem. On that note, how do you configure the XS to work with a proxy server? http://wiki.laptop.org/go/XS_Techniques_and_Configuration#HTTP_proxies this may help Thanks. Gerald On Tue, Feb 1, 2011 at 4:22 PM, Martin Langhoff martin.langh...@gmail.com wrote: On Mon, Jan 31, 2011 at 1:15 PM, Dr. Gerald Ardito gerald.ard...@gmail.com wrote: I am trying to connect XOs in a school which as a wireless network with a hidden SSID. Additionally, the school requires proxy settings to establish internet connections. Can someone help me with this? Very tricky. The Sugar side won't wandle this situation very well at all. GNOME can handle it. Under Sugar - You may be able to set the proxy setting with a pac file. Pia Waugh reported once that it worked with 8.2.1, but I don't think she documented it. - Hidden SSIDs are not handled well at all by Sugar's network neighbourhood. cheers, m -- martin.langh...@gmail.com mar...@laptop.org -- Software Architect - OLPC - ask interesting questions - don't get distracted with shiny stuff - working code first - http://wiki.laptop.org/go/User:Martinlanghoff ___ support-gang mailing list support-g...@lists.laptop.org http://lists.laptop.org/listinfo/support-gang -- Abrazoss.. One Laptop Per Child - http://wiki.laptop.org/go/User:Kevin.benavides -- Voluntary sugarlabs Implementation of SOAS http://wiki.sugarlabs.org/go/User:Kevin.benavides ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: [Server-devel] Hidden SSID and Proxy settings
This wouldn't happen to be in NYC, would it? I remember reading a long time ago that the schools there have a policy that SSIDs can't be broadcast. You might deter my Grandma with that, but it's almost pointless as a security measure. http://olpcnyc.wordpress.com/2008/05/09/connecting-to-hidden-wifi-networks/ That workaround is likely deprecated now, though. If this is a newer image, one based on F11 then you should be able to use nmcli to connect. Take a look at this page. http://blog.nixpanic.net/2011/01/connect-automatically-and-immediately.html Hope that helps. My grandma would still hack it in 2 seconds though :-) Jon ___ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
Re: [Server-devel] Hidden SSID and Proxy settings
On Mon, 2011-01-31 at 15:15 -0500, Dr. Gerald Ardito wrote: I am trying to connect XOs in a school which as a wireless network with a hidden SSID. Additionally, the school requires proxy settings to establish internet connections. Can someone help me with this? Can you tell us what os version is installed on the XOs? Jerry ___ Server-devel mailing list Server-devel@lists.laptop.org http://lists.laptop.org/listinfo/server-devel
Re: [Server-devel] Hidden SSID and Proxy settings
Jerry, I am not sure. It is whatever version they were shipped with. They are XO 1.5s, and they arrived in October. I am not where they are, so I can't check the version. Thanks. Gerald On Tue, Feb 1, 2011 at 8:57 AM, Jerry Vonau jvo...@shaw.ca wrote: On Mon, 2011-01-31 at 15:15 -0500, Dr. Gerald Ardito wrote: I am trying to connect XOs in a school which as a wireless network with a hidden SSID. Additionally, the school requires proxy settings to establish internet connections. Can someone help me with this? Can you tell us what os version is installed on the XOs? Jerry ___ Server-devel mailing list Server-devel@lists.laptop.org http://lists.laptop.org/listinfo/server-devel
Re: [Server-devel] Hidden SSID and Proxy settings
On Tue, 2011-02-01 at 09:11 -0500, Dr. Gerald Ardito wrote: Jerry, I am not sure. It is whatever version they were shipped with. They are XO 1.5s, and they arrived in October. I am not where they are, so I can't check the version. I'd upgrade the os to the latest version (os860) before you try configuring anything on the XO. Jerry ___ Server-devel mailing list Server-devel@lists.laptop.org http://lists.laptop.org/listinfo/server-devel
Re: [Server-devel] Hidden SSID and Proxy settings
Jon, The school is in NYC, the land of hidden SSIDs. I will check out this page and try to make it work in the school. And, congrats to your grandma. Thanks. Gerald On Tue, Feb 1, 2011 at 4:43 PM, Jon Nettleton jon.nettle...@gmail.comwrote: This wouldn't happen to be in NYC, would it? I remember reading a long time ago that the schools there have a policy that SSIDs can't be broadcast. You might deter my Grandma with that, but it's almost pointless as a security measure. http://olpcnyc.wordpress.com/2008/05/09/connecting-to-hidden-wifi-networks/ That workaround is likely deprecated now, though. If this is a newer image, one based on F11 then you should be able to use nmcli to connect. Take a look at this page. http://blog.nixpanic.net/2011/01/connect-automatically-and-immediately.html Hope that helps. My grandma would still hack it in 2 seconds though :-) Jon ___ Server-devel mailing list Server-devel@lists.laptop.org http://lists.laptop.org/listinfo/server-devel
[Server-devel] Question on number of iptables rules
My test XS at home has a FQDN and is open to the outside. Therefore this is probably a pretty rare issue in XS land, but I thought I'd ask. I noticed my ambient rx/tx traffic on eth0 had gone from really low (like 0.1 to 0.7 kB/s) to hovering between 5-20 kB/s. I went through httpd's access_log and error_log and blocked a bunch of IPs that looked kinda sketchy. Chinese and Russian search engine bots, script kiddies looking for phpmyadmin, that kinda stuff. Of course, I do have robots.txt disallowing all user agents, but we know that's not always respected. Then I thought, rather than play whack-a-mole with individual IPs, I'll just block China and Russia altogether. However, that brings up another question. Between China: http://www.wizcrafts.net/chinese-iptables-blocklist.html and Russia: http://www.wizcrafts.net/russian-iptables-blocklist.html that's a ton of IP addresses. Getting them into /etc/sysconfig/olpc-scripts/iptables-xs is easy enough. I pasted the IP data into a file named banned_ips.txt and ran this little script: #!/bin/bash for i in $( banned_ips.txt); do iptables -A INPUT -s $i -j DROP done I didn't mess with iptables-xs.in, as I figured I might need to update and/or straighten stuff out and a simple IP list is a lot easier to manipulate. Of course, restarting iptables reloads iptables-xs.in and the block list is gone from iptables-xs. No big deal, as the above script just takes a couple seconds to run and they're back in there. Here's my question - is the XS networking going to get wonky with 894 extra iptables rules? I know every incoming connection has to be checked against it, so what's the max count of rules that's a good idea? And is there a better way to handle this? Anna Schoolfield Birmingham P.S. After blocking all these IPs, my ambient traffic has gone back down to normal. ___ Server-devel mailing list Server-devel@lists.laptop.org http://lists.laptop.org/listinfo/server-devel
Re: [Server-devel] Question on number of iptables rules
On Tue, Feb 1, 2011 at 5:28 PM, Anna ascho...@gmail.com wrote: My test XS at home has a FQDN and is open to the outside. Therefore this is probably a pretty rare issue in XS land, but I thought I'd ask. I noticed my ambient rx/tx traffic on eth0 had gone from really low (like 0.1 to 0.7 kB/s) to hovering between 5-20 kB/s. I went through httpd's access_log and error_log and blocked a bunch of IPs that looked kinda sketchy. Chinese and Russian search engine bots, script kiddies looking for phpmyadmin, that kinda stuff. It can help to block China and Russia but the way spam and denial of service botnets work that is more limited than you might wish. Two tools denyhosts and PortSentry come to mind. They will deal with many blunt script attacks that come from anyplace on the globe even Iceland ;-) With a system live on the internet it is often valuable to block everything first and then open exactly what you need for exactly those that need it. The number of rules by itself almost does not matter. Sometimes the order of rules matters more. For example you can drop/block all connections to telnet and many other port services in a very early rule and never need to test your long list of IP address blocks. Log files always need to be watched. -- T o m M i t c h e l l mitch-at-niftyegg-dot-com My lifetime goal is to be the kind of person my dogs think I am. ___ Server-devel mailing list Server-devel@lists.laptop.org http://lists.laptop.org/listinfo/server-devel
Re: [Server-devel] Question on number of iptables rules
On Tue, Feb 1, 2011 at 8:46 PM, Tom Mitchell mi...@niftyegg.com wrote: It can help to block China and Russia but the way spam and denial of service botnets work that is more limited than you might wish. Well, I'm not currently running a mail server, so luckily I don't have to worry about that right now. The Chinese and Russian stuff was in my httpd logs. And quite a bit of it, which gave me concern enough to want to block those two countries. I read that a lot of other server admins take a similar approach. Two tools denyhosts and PortSentry come to mind. They will deal with many blunt script attacks that come from anyplace on the globe even Iceland ;-) I'm running ssh on a non standard port, and have never seen any attacks in /var/log/secure. Not sure how denyhosts is supposed to help me there. As far as port scanning, I try to keep available ports to a bare minimum. I did look into Fail2ban, but since my issue seemed to be mostly Apache related, and the individual IPs varied quite a bit among the Chinese and Russian ranges, I can have tons of unwanted traffic before that kicks in. With a system live on the internet it is often valuable to block everything first and then open exactly what you need for exactly those that need it. So when I get weird stuff on port 80, I'm supposed to block the entire internet from my web server except my friends and my Mom? If I ask my Mom her IP address, she's likely to give me her phone number. Or maybe run Apache on a random port? Hey, y'all, when you try to go to my schoolserver, just remember it's http://schoolserver.example.org:4329; Not likely. The number of rules by itself almost does not matter. Sometimes the order of rules matters more. In iptables, I've got a few lines of regular stuff and then 894 drop statements for the IP ranges that are likely going to be problematic. Not sure what kind of order almost 900 drop statements are supposed to be in. For example you can drop/block all connections to telnet and many other port services in a very early rule and never need to test your long list of IP address blocks. The XS 0.6 doesn't ship with telnet and no one uses that any more anyway. All I have open to the outside world are ports for Apache, Jabber, and ssh. And my ssh port is non-standard and doesn't show up on a casual nmap -sS anyway. Again, never any issues logged as far as script kiddies poking around at ssh. And I do keep tabs on who's registered to the Jabber server. If I run ejabberdctl stats registeredusers and there's a ridiculous number, I can take a look at the web admin interface to see specifics. And then there are folks on my Jabber server pretty much 24/7 and I have all the chat rooms logged. I posted here because I wanted to know if 894 rules in iptables-xs was going to be a problem on XS 0.6. And if there was a better way to handle the issue. Log files always need to be watched. I do agree with you there. I try to look in on my httpd logs every couple of days. And the XS 0.6 logwatch emails are quite informative. I installed alpine, so keeping up with them is fast and simple. Anna Schoolfield Birmingham ___ Server-devel mailing list Server-devel@lists.laptop.org http://lists.laptop.org/listinfo/server-devel
