Re: [SLUG] Replicate Production to DR file system with rsync
On 13/02/2010, at 11:42 AM, Ken Foskey wrote: I use a simpler approach and to some extent more flexible. I create a script in a known directory, for example /usr/sbin/run_copy.sh. I then only authorise the admin group to run only that specific script. This keeps complicated command lines to a minimum. The run_copy command might for example do a tar of the specified files. You can then pipe that tar across the link to the recipient system. I would write another script to untar into a working set, verify the copy somehow then install it using another script. visudo add this line # allow admin group to run the rsync script %admin ALL=NOPASSWD: /usr/sbin/run_copy.sh Hi Ken, Thanks for the suggestion. Unfortunately this incurs the penalty of copying everything, every time (unless I missed something). Hence the desire to use rsync. I guess if I didn't do anything special (like encrypting) the tar ball, rsync could still handle the deltas with a certain degree of efficiency, but it would mean doing an update on the tar file each time. Total data requiring synchronisation is approx 12GB, every 15-30min...that's a heck of a lot of I/O and network bandwidth if rsync doesn't do a stellar job. I also noticed a --super option in the rsync manual, but I don't really understand how this works or what it achieves. On the upside, I've had an e-mail discussion with the notoriously suspicious Security Team and they have agreed (in principle) to relaxing the no remote root login by allowing the use of PermitRootLogin Forced-Commands-Only in sshd_config coupled with the method described here http://troy.jdmz.net/rsync/index.html - sanity and sensibility prevail. Now to go through the motions of change control and security approval. Ugh. Why is nothing easy? :( Thanks for all the input people. Cheers, James smime.p7s Description: S/MIME cryptographic signature -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] removing custom kernel
On Sat, 2010-02-13 at 19:45 +1100, david wrote: Is it reasonable to do # dpkg -r to remove the custom kernel/headers? I would say so. or is that likely to cause grief? I'd really like to be able to reboot afterwards ;-) As long as your current kernel is present in /boot, and you verify that it's still there after you `dpkg -r` the old kernel, you should be fine. If you're really nervous, re-run `apt-get install linux-image-generic` after you `dpkg -r` just to make sure. :) signature.asc Description: This is a digitally signed message part -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] Replicate Production to DR file system with rsync
On Sun, 2010-02-14 at 20:04 +1100, James Gray wrote: On 13/02/2010, at 11:42 AM, Ken Foskey wrote: I use a simpler approach and to some extent more flexible. I create a script in a known directory, for example /usr/sbin/run_copy.sh. I then only authorise the admin group to run only that specific script. This keeps complicated command lines to a minimum. The run_copy command might for example do a tar of the specified files. You can then pipe that tar across the link to the recipient system. I would write another script to untar into a working set, verify the copy somehow then install it using another script. visudo add this line # allow admin group to run the rsync script %admin ALL=NOPASSWD: /usr/sbin/run_copy.sh Hi Ken, Thanks for the suggestion. Unfortunately this incurs the penalty of copying everything, every time (unless I missed something). Hence the desire to use rsync. I guess if I didn't do anything special (like encrypting) the tar ball, rsync could still handle the deltas with a certain degree of efficiency, but it would mean doing an update on the tar file each time. Total data requiring synchronisation is approx 12GB, every 15-30min...that's a heck of a lot of I/O and network bandwidth if rsync doesn't do a stellar job. I also noticed a --super option in the rsync manual, but I don't really understand how this works or what it achieves. On the upside, I've had an e-mail discussion with the notoriously suspicious Security Team and they have agreed (in principle) to relaxing the no remote root login by allowing the use of PermitRootLogin Forced-Commands-Only in sshd_config coupled with the method described here http://troy.jdmz.net/rsync/index.html - sanity and sensibility prevail. Now to go through the motions of change control and security approval. Ugh. Why is nothing easy? :( Thanks for all the input people. Cheers, James You can still use rsync. You just write rsync command in the script as per above. Ta Ken -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
[SLUG] What I want for Christmas...
http://mashable.com/2010/02/11/google-liquid-galaxy-video/ Linux reference at 2mins 33secs Whooo ho! Patrick -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] Replicate Production to DR file system with rsync
Has anyone suggested using setuid? Why don't you write a program to do the backup. Set ownership root, group to backup, chmod 770 and then setuid on the program and you can remote login as the backup group and execute the program with root privileges to do just the things you put in the code. If this isn't acceptable to the security team then you'd better also disable the password program. Just a thought. Pete -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
[SLUG] SLUG February Monthly Meeting - Python Game Programming *Tutorial*
Some corrections and clarifications: * The date is Friday 26 February. We need to start at 6:30pm sharp in order to complete the tutorial on time. * The address is Google Australia, Level 5, 48 Pirrama Road, Pyrmont. It is across the road from Star City Casino. Apologies for the inconvenience. Please make sure of the following: * Sign up through Eventbrite so that we can properly plan space and facilities: http://slug.eventbrite.com * You have a laptop set up with the requisite libraries *before* the workshop begins * I have added instructions for setting up with Fedora and OLPC XO * Please contribute to the wiki page with directions for setting up in other environments * If you need assistance, show up early Thanks, Sridhar -- Forwarded message -- From: Tim Ansell mit...@mithis.com Date: 12 February 2010 05:54 Subject: [activities] SLUG FebruaryMonthly Meeting - Python Game Programming *Tutorial* To: annou...@slug.org.au Cc: slug@slug.org.au, activit...@slug.org.au You can read the full version of this announcement at http://slug.org.au/node/123 == Summary == Date: Friday 29nd of January (Friday next week). Start Time: Arrive at 6:15pm for a 6:30pm *sharp* start Format: Python Game Programming, BOFs, Pizza Dinner Where: Google Australia, opposite Star City *** You will need a setup laptop to participate in this tutorial. ** * Instructions for setting up your laptop are listed at http://wiki.slug.org.au/pythonprogrammingsetup == SLUG January Monthly Meeting == Instead of running two 45 minute talks will be having two Python game tutorials. At the end of each tutorial you should have a fully playable game developed and running! The first tutorial will be suitable for beginners of all ages, no programming experience will be required. The tutorial will focus around a Punch the Monkey game, but there should also be enough meat for more advanced people to create something cool. The second tutorial will be suitable for people who want to advanced further and will concentrate on extending skills learnt in the earlier tutorial. Some programming experience is recommended for this tutorial. During this tutorial people will create a clone of either space invaders or asteroids. As the tutorials will be interactive you will need to bring a laptop. You will also need to set-up your laptop with the appropriate software. The software runs on Linux, Mac and Windows. You will need to install: * Python - http://python.org * Pyglet - http://pyglet.org * Rabbyt - http://matthewmarshall.org/projects/rabbyt/ To test that everything works, I have included a small Python program which will display It works if everything is working. To do so on Ubuntu, you would use the following commands; # Install python and easy_install apt-get install python python-setuptools # Install pyglet and rabbyt easy_install pyglet easy_install rabbyt # Test everything is working python test.py If you figure out instructions for other operating systems or Linux versions please add them at: http://wiki.slug.org.au/pythonprogrammingsetup *** If you have problems, please turn up **early** so we can fix them! = Meeting Details = SLUG is the very mis-named Sydney Linux User Group. We are a general Open Source interest group which runs our primary event on the last Friday of every month (except December). Meetings are open to the general public, and are free of charge. Our venue is Google, Level 5, 48 Pirrama Road, Pyrmont. It's across the road from Star City Casino. A map of the area can be found here[1], and public transit directions are at [2]. Appropriate signage and directions will be posted around the building. You will need to sign-in to enter the venue. This can be performed when you arrive, but to save time we recommend that you do so online beforehand at Eventbrite ( http://slug.eventbrite.com ). If you are unsure, please sign up as a 'maybe'. This allows us to organise adequate meeting space and facilities. You do not need to create an account to indicate your attendance. = Meeting Schedule = We start at 18.30 but we ask that people arrive at least 15 minutes early so we an all get into the building and start on time. Please do not arrive before 18.00, as it may hinder business activities for our host! See here[5] for an explanation of the segments. * 18.15: Open Doors * 18.30: Announcements, News, Introductions * 18.45: General Talk * 19.30: Intermission * 19.45: In-Depth Talk * 20.30: Dinner BoFs and the Hackerspace run from the time the doors open. = Bird of a Feather (BoF) Sessions = The list of BoFs at the moment are: * SLUGlets - our regular forum for newbies and desktop users If you would like to run a BoF, please discuss on the SLUG Activities mailing list[4]. = Hacker Space = We have heaps of room available to us at Google. If the talks do not grab you, feel free to come along and hack away on
[SLUG] Earliest open source?
What's the earliest reference to open source anyone knows? I found this in a 1965 paper: The Multics system will be published when it is operating substantially, and will therefore be available for implementation on any equipment with suitable characteristics. Such publication is desirable for two reasons: First, the system should withstand public scrutiny and criticism volunteered by interested readers; second, in an age of increasing complexity, it is an obligation to present and future system designers to make the inner operating system as lucid as possible so as to reveal the basic system issues. (From: Corbato and Vyssotsky, `Introduction and Overview of the MULTICS system' proc. fall joint computer conference, 1965. http://www.multicians.org/fjcc1.html ) (Oh, and the Mulicts system *is* published: see http://web.mit.edu/multics-history/ Mind you, even though the intention was for the source to be open-source, the development process was closed-source, and ran very very late... so th source wasn;t released until 1999, 15 years after development stopped...) -- Dr Peter Chubbwww.nicta.com.au peter DOT chubb AT nicta.com.au http://www.ertos.nicta.com.au ERTOS within National ICT Australia From Imagination to Impact Imagining the (ICT) Future -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] Earliest open source?
On Mon, 2010-02-15 at 09:05 +1100, Peter Chubb wrote: What's the earliest reference to open source anyone knows? I found this in a 1965 paper: How like Unix does the following story sound? Open Source (not as a name) existed in IBM in the old mainframe systems. Systems Programmers, who are now systems administrators, were hard core programmers. IBM had (from memory) Share tapes which was supplied by an independent group of users called share(?). Programmers wrote useful utilities and sent in this code. The code went to the various systems programmers on tape who used this code, enhanced and sent it back. This code was shared between sites. I think that TSO (Time Share Option) started like this originally however I may be wrong. TSO was a command line for Mainframe which was batch oriented until then, yes punched cards. Systems Programmers also worked on the Operating System itself. While it was proprietary the source was supplied and the Systems Programmers patched the source and returned the patches to IBM. I believe that the reason it became the most stable system available was the bazaar of programmers on installed systems, not the cathedral of IBM support. As a sideline the source was effectively stolen by another vendor who created a competing system. There was a lot of politics and there was a really strange settlement. IBM was forced to share the source with the other vendor by the US government. Ken -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
[SLUG] Re: Earliest open source?
Peter What's the earliest reference to open source anyone knows? I found this in a 1965 paper: The Multics system will be published when it is operating substantially, and will therefore be available for implementation on any equipment with suitable characteristics. Yes. This fits in with everything that I have read and seen for the past 30 years. I suppose that it might sound strange to anyone else but even back in 1974 when I was working next to one of the first ICL commercial computers here in Sheffield there were people around me talking about ideas that are like open source software of the present day. Many open source ideas have come and gone. The present day version is probably the purest version (maybe). Uuuhhmmm Linux ? Yeh.. it's a word I thought up back in 1982 when I was in the Royal Air Force after I found out that UNIX was in need of something better. Why it took Linus 13 years to write the code for the word I had invented when I worked on the Nimrod re-fuelling protect I do not know... http://en.wikipedia.org/wiki/Hawker_Siddeley_Nimrod Sadly, we lost some of our friends from Oz while I was working on this :( We still miss them now (lest we forget?) Richard http://www.sheflug.org.uk http://www.linuxuser.co.uk/news/knoppix-founder-klaus-knopper-speaks/ -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
[SLUG] Re: slug Digest, Vol 49, Issue 18
On Sunday 14 February 2010 22:25:18 slug-requ...@slug.org.au wrote: [snip] The computer was warm enough to keep your coffee warm, so there is still an issue. I am not going to get aircon any time soon. I was reading that you can use air conditioning filter over the inlets to collect the dust so your case is cleaner. I can only see this working with a positive pressure fan drawing air from outside to inside. Is is worth putting a fan in the case to blow into with a filter on it? After all the work you have done :-) ... AMD really runs cool [eeyore] /home/jam [54]% ssh tigger cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 15 model : 107 model name : AMD Athlon(tm) X2 Dual Core Processor BE-2300 stepping: 1 cpu MHz : 1000.000 ... [eeyore] /home/jam [55]% ssh tigger temp fan1: 1700 RPM (min = 10 RPM) fan2: 0 RPM (min =0 RPM) temp1: +40.0°C # CPU temp2: +32.0°C # MB ... Ambient 28.9 C Even at 5% idle I've never seen it over 50 James -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] Re: Earliest open source?
Richard Ibbotson wrote: What's the earliest reference to open source anyone knows? I found this in a 1965 paper: The Michigan Terminal System (MTS) emerged in the early 70s, with the source code shared and maintained by a number of unis. http://www.everything2.com/index.pl?node_id=1404097lastnode_id=0 The Michigan Terminal System (MTS) was an IBM mainframe compatible operating system which came out of the University of Michigan in the early 1970s. MTS was developed and maintained by a consortium of universities around the world including ... http://www.clock.org/~jss/work/mts/timeline.html May 1967 MTS released to campus as operating system for IBM 360/67. November 1968 University of British Columbia runs MTS And elsewhere http://www.clock.org/~jss/work/mts/overview.html: Whereas other systems made users feel like it was just them one-on-one with a computer, MTS was designed with many features that enabled sharing and collaboration. Users were able to collaborate with MTS developers, and vice versa. According to Bob Parnes, architect of the Confer system, 'MTS was our system; it belonged to the University, not to a corporation.' Other refs: http://www.cis.udel.edu/~mills/gallery/gallery8.html http://en.wikipedia.org/wiki/Michigan_Terminal_System cheers rickw -- _ Rick Welykochy || Praxis Services No position is so absurd that a philosopher cannot be found to argue for it. -- Michael Lockwood -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
[SLUG] Hot computer
On Mon, 2010-02-15 at 08:43 +0800, james wrote: On Sunday 14 February 2010 22:25:18 slug-requ...@slug.org.au wrote: [snip] The computer was warm enough to keep your coffee warm, so there is still an issue. I am not going to get aircon any time soon. I was reading that you can use air conditioning filter over the inlets to collect the dust so your case is cleaner. I can only see this working with a positive pressure fan drawing air from outside to inside. Is is worth putting a fan in the case to blow into with a filter on it? After all the work you have done :-) ... AMD really runs cool [eeyore] /home/jam [54]% ssh tigger cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family: 15 model : 107 model name: AMD Athlon(tm) X2 Dual Core Processor BE-2300 stepping : 1 cpu MHz : 1000.000 ... [eeyore] /home/jam [55]% ssh tigger temp fan1: 1700 RPM (min = 10 RPM) fan2: 0 RPM (min =0 RPM) temp1: +40.0°C # CPU temp2: +32.0°C # MB ... Ambient 28.9 C Even at 5% idle I've never seen it over 50 My ambient at the time was about 30 plus inside my house. My house is a hot box, I am planning renovations so it is here to stay for 12 months at least. My GPU is HOT, 50 degrees. That would contribute. Should have gone with a simpler passive one in hindsight. Ta Ken -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] Replicate Production to DR file system with rsync
On Monday 15 February 2010 09:00:05 slug-requ...@slug.org.au wrote: Has anyone suggested using setuid? Why don't you write a program to do the backup. Set ownership root, group to backup, chmod 770 and then setuid on the program and you can remote login as the backup group and execute the program with root privileges to do just the things you put in the code. If this isn't acceptable to the security team then you'd better also disable the password program. Just a thought. setuid does not work on modern distros umm pam limits applies http://www.mythtv.org/docs/mythtv-HOWTO-5.html#ss5.4 (enabling real time priority) James -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
Re: [SLUG] Earliest open source?
On Monday 15 February 2010 09:00:05 slug-requ...@slug.org.au wrote: What's the earliest reference to open source anyone knows? I found this in a 1965 paper: The Multics system will be published when it is operating substantially, and will therefore be available for implementation on any equipment with suitable characteristics. Such publication is desirable for two reasons: First, the system should withstand public scrutiny and criticism volunteered by interested readers; second, in an age of increasing complexity, it is an obligation to present and future system designers to make the inner operating system as lucid as possible so as to reveal the basic system issues. (From: Corbato and Vyssotsky, `Introduction and Overview of the MULTICS system' proc. fall joint computer conference, 1965. http://www.multicians.org/fjcc1.html ) (Oh, and the Mulicts system is published: see http://web.mit.edu/multics-history/ Mind you, even though the intention was for the source to be open-source, the development process was closed-source, and ran very very late... so th source wasn;t released until 1999, 15 years after development stopped...) Cica 1980 I obtained and built emacs James -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
[SLUG] WINMOR -- a win for free protocols
Hi, This may interest some, bore others, and remind others of the time when *all* modem communication was slow: http://www.winlink.org/WINMOR Traditionally, digital communication over long distance radio has been slow and expensive. Slow of necessity because the carrier radio waves for the digital signal are typically in the 2MHz - 16MHz frequency range and therefore don't carry significant amounts of digital information per second (10 - 100 bytes per second are typical of the technology), and expensive because of a proprietary protocol and product called PACTOR that requires a specific make model of HF modem to interface between the PC and the HF radio set. However for long distance communication between HAM radio enthusiasts and vessels at sea, it's the only option. Other than satellite, which for vessels at sea takes expensive to new levels of meaning (it's difficult to arrange a fixed satellite dish on a ship that's moving and pitching in all directions), there are no other means of communicating. The higher frequency spectrums that carry digital signals to users of mobile broadband just don't have that sort of propagation. The PACTOR protocol is covered by several patents which make it impossible for third party vendors to implement this protocol. So everyone who wants to use this is stuck with the expensive and proprietary PACTOR modems, along with their proprietary (and MS Windows only) software to drive them. There is a new protocol and software under test called WINMOR, developed by the Winlink 2000 folks who traditionally provide an endpoint for digital communications with amateur stations and vessels at sea. Although the current software is available for Windows only, the protocol and specification have been released to the public domain for anyone to implement. Although the protocol and software are both under development, the end product has been shown to be reasonably stable and reliable. The only hardware required is a sound card, and of course an HF or HAM radio (nearly all ships would have the latter as an essential piece of safety equipment). There are a number of WINMOR enabled HF stations worldwide, with more popping up regularly, including 2 so far in Australia. Remember that HF propagation, depending on the frequency chosen, time of day, solar activity, number of sunspots, etc, can be anything from 200km to planet-wide, so for global communications to be effective over this type of network there is no significant need for large numbers of stations. -- Del Babel Com Australia http://www.babel.com.au/ -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
