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Re: [ALUG] OT Maths Jam
by Steve Engledow 21 Aug '12

21 Aug '12

Morning all, I've been in conversation with the maths jam organising folks and... Norwich maths jam is go! I'm in the process of setting up a mailing list so if you want in, please email norwich(a)mathsjam.com and I'll make sure you're on it. I'll send emails out from that address once a venue has been confirmed etc. The maths jam is on the second-to-last tuesday of the month which makes the 1st Norwich jam the 18th September. Whether you're interested or not, please forward this email onto anyone you think might be. Steve ----- Forwarded message from Steve Engledow <steve(a)offend.me.uk> ----- Date: Tue, 24 Jul 2012 22:20:03 +0100 From: Steve Engledow <steve(a)offend.me.uk> To: main(a)lists.alug.org.uk Subject: OT Maths Jam Hi folks, Would anyone be interested in a Norwich maths jam? See http://www.mathsjam.com/ for (fairly vague) details or check the twitter account (@MathsJam). tl;dr: We get together in a pub on the second-to-last tuesday of the month and be geeky. I know, it sounds like the pubmeet; but this time we be geeky about mathsy things! I reckon there ought to be enough maths geeks among the linux geeks for this to be relevant :) Steve ----- End forwarded message -----

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[ALUG Announce] 3rd Monday Monthly Ipswich Social Meeting : The Mulberry Tree
by samwise 20 Aug '12

20 Aug '12

ALUG Announce Please send announcements to Announce(a)lists.alug.org.uk Unsub, change settings via http://lists.alug.org.uk/mailman/listinfo/announce ----- The monthly "Third Monday" ALUG Ipswich Social Meeting is back tonight - Monday, 20th August, at 20:00: The Mulberry Tree 5 Woodbridge Road IPSWICH IP4 2EA Tel: 01473 225776 Map/Directions URI: http://maps.google.co.uk/?q=IP4+2EA WWW: https://www.facebook.com/MULBERRYHOSPITALITY The Mulberry Tree, previously known as The Milestone Beer House, is a grade 2 listed building in the centre of Ipswich. It is located at the intersection between Woodbridge Road and the A1156, across the road from the old Odeon cinema and not far from the Regent Theatre. It re-opened on Thursday March 29th 2012 after a major refurbishment, under its original name of The Mulberry House and has already begun to regain a good reputation for its selection of beers and ales. It has a sizeable car park to the rear of the building. All are welcome, novices and experienced users. Feel free to ask for further information on the Main ALUG mailing list. Oops. Apologies for the late notice - I've been pretty busy most of the day. Anyway, I intend to make it out tonight and will probably be soliciting advice from anyone who's got any recommendations for what to try out with rooted Android devices. Peter. ----- Send discussion replies to main(a)lists.alug.org.uk (Reply-To set) Unsub, change settings via http://lists.alug.org.uk/mailman/listinfo/announce

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Android updates for cheap tablet
by Mark Rogers 20 Aug '12

20 Aug '12

I have a cheap Android tablet, branded Synapse, I think it's this model although I paid nothing like that for it: http://www.dee-sign.co.uk/products/synapse-tablet-top-spec What are my options for playing with Android versions? I'd like to experiment with (eg) CyanogenMod but haven't done it before; I was thinking it better to risk my cheapo tablet than my Galaxy SII but on the other hand at least the GS2 has been well tested... I believe the tablet is just the same as any number of cheap imported tablets and I don't want it to be stuck on the version it shipped with (albeit that it came with ICS). -- Mark Rogers // More Solutions Ltd (Peterborough Office) // 0844 251 1450 Registered in England (0456 0902) 21 Drakes Mews, Milton Keynes, MK8 0ER

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Keyboard and mouse 'crash'
by Bev Nicolson 19 Aug '12

19 Aug '12

Every so often (not too often happily) both keyboard and mouse will stop functioning. It seems to happen most often when I plug a camera or MP3 player in. The only way to get them going again is to switch everything off. (If I touch the off button it will shut down in 60 seconds from the shut down dialogue box.) What I'm wondering is, has anyone here come across this problem and is there another, more permanent, solution to it? I would add that I've never had to install any drivers for any such devices, so I'm pretty confident that's not the issue. [Unbuntu 11.04.] Bev.

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Wanted - algorithm for bufferless search for a pattern in a stream
by Chris Green 08 Aug '12

08 Aug '12

I can see how to do this in principle but I can't iron out the details and I'm sure there must be some ready made code for doing it 'out there' on the internet. It's just rather difficult to come up with search terms when I don't know what to call it. To explain in detail I want to search for a (constant) string in a byte stream that I can't rewind and I don't want to use any significant buffer space (the constant string I'm looking for is quite long). So, obviously one reads a byte at a time from the stream to see if it matches the first character of the constant string, if that matches one moves on to the second, etc. When the whole string has been matched then it's found - so far so good. However, when a character *doesn't* match one can't go back up the input stream, *but* we know the previous characters as they're the ones in the constant string that we have matched so far. Thus we can 'wind back' by using the constant string for the number of characters that did match and then continue down the stream. If anyone can follow that rubbish explanation then could they possibly tell me what the algorithm is called and/or point me at some sample code? -- Chris Green

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[ALUG Announce] ALUG Norwich Pub Meet Thursday 9th August
by Viperfang 06 Aug '12

06 Aug '12

ALUG Announce Please send announcements to Announce(a)lists.alug.org.uk Unsub, change settings via http://lists.alug.org.uk/mailman/listinfo/announce ----- Hello Norwich Aluggers, Our monthly ALUG Norwich social meeting will be held this Thursday, 9th August at The Coach and Horses (82 Thorpe Road, Norwich, NR1 1BA). The meeting officially starts at 8pm, although some people may arrive earlier. More information on those people can be found on the list and the IRC channel. If you are unsure if you will recognise us then make yourself and your intent to attend known by either posting on list or visiting us on IRC so we can look out for you rather than hiding in the corner. Optionally you could ask at the bar if they know where the geeky computer weirdos are and they'll point you in the right direction (seriously!). Another possibility is look for heaps of electronics on a table that may possibly look like movie props that would used for detonating explosives. Feel free to bring electronics/laptops/gadgets to the meet, you will by no means be alone. Ben Bewick aka Viperfang NB: This mail is automated, please refer to the usual sources for more information. ALUG Contact Details: Website : http://www.alug.org.uk/ IRC : #alug on irc.alug.org.uk List : http://lists.alug.org.uk/mailman/listinfo Twitter : http://twitter.com/anglianlug Identica: TBA Facebook: http://www.facebook.com/group.php?gid=2381613902 ----- Send discussion replies to main(a)lists.alug.org.uk (Reply-To set) Unsub, change settings via http://lists.alug.org.uk/mailman/listinfo/announce

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Forcing "Sender:" in exim4
by Ted.Harding＠wlandres.net 05 Aug '12

05 Aug '12

Greetings All! I have just (!!! -- after about 4 years ... !!!) that in my Debian Etch setup 'sendmail' is aliased to 'exim4': ls -l `which sendmail` /usr/sbin/sendmail -> exim4 My mailer (MUA) setup presumes sendmail. I have configured the MUA so that, in the headers for outgoing mail, I have set: Sender: ted.harding@wlandres (same as my "From:" and "Reply-To:" addresses). That is how the header appears while the message is still in the "outbox" folder. However, when I send the mail out, it seems that exim4 changes the "Sender:" address to "ted@deb", "deb" being the name of my machine on my home LAN (as set in /etc/hosts), and "ted" being the user. As a result, when the mail is received outside my LAN, the receiving host sees the header: Sender: ted@deb instead of what I want it to be! This sometimes results in rejection when the receiving host does not recognise the sender domain. Now, while I know my way round sendmail itself, I find I am disorientated by trying to make out how to customise exim4 configuration. (I've tried reading the man pages). What I want to do is ensure that exim4 (aliased as 'sendmail') either does not change the "Sender:" header as it is while still in the outbox, or else sets it anyway to Sender: ted.harding(a)wlandres.net And it could also be useful, though not essential, if, should I happen to mail as a different user on the same machine, e.g. "efh", it could preserve the domain and insert the user, e.g. Sender: efh(a)wlandres.net My mind is blank about how to set about configuting exim4, so I need very basic instructions (preferably with outline explanation). Maybe a configuration file (where and how?) change, or a command line option to exim4 (the latter is probably simpler for me, since I can enter such options in my MUA setup). With thanks! Ted. ------------------------------------------------- E-Mail: (Ted Harding) <Ted.Harding(a)wlandres.net> Date: 04-Aug-2012 Time: 17:07:50 This message was sent by XFMail -------------------------------------------------

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For Pi users
by nev young 03 Aug '12

03 Aug '12

Something that may be of interest to both ALUG and 2600 members is this magazine (it's free) for the Raspberry Pi. The url is http://www.themagpi.com Nev

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LAN traffic sniffing/monitoring - good tools and methods - help wanted
by Chris Green 31 Jul '12

31 Jul '12

I want somehow (if it's possible) to monitor the packets going into and out of one ethernet address/MAC address on my LAN. I think it's currently plugged into a port on my 8-port Gigabit switch but I'm not absolutely sure of that. The LAN comprises a Draytek Vigor ADSL router talking to the outside world and a Linksys 8-port Gigabit router with most of my LAN systems plugged into that. I think a couple of the four ports on the ADSL router may be in use in addition to the one that connects to the 8-Port Gigabit switch. Is there any 'easy' way to monitor all traffic to/from one specific IP address on the LAN from my desktop computer or will the switches on the LAN prevent it seeing most of the traffic? Actually even being able to see all traffic between my desktop and the device I'm interested in would probably be sufficient as 'lack of traffic' might well be enough to tell me what I want to know. So what are the best/easiest packet sniffers to run on a desktop machine that would allow me to 'see' all traffic to/from a specific IP address? -- Chris Green

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2600 meeting at 18:00 on Friday the 3rd August.
by Viperfang 31 Jul '12

31 Jul '12

Quick heads up about this months Norwich 2600 meeting, more info at http://www.norwich2600.co.uk

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Xen and OOM killer
by Richard Lewis 30 Jul '12

30 Jul '12

Hi ALUG, I've been managing a Xen hypervisor for about nine months now and occasionally I get problems with DomUs running out of memory. The clients are all students and most of them are running WordPress blogs. The instances of OOM errors I've seen seem to be related to Apache and students serving up large image files. I'm thinking that this shouldn't really be happening; serving up a few ~1MB files shouldn't really be causing Apache to make the OS exhaust *all* available memory, should it? Even if it were servicing several requests simultaneously. Some details: * The host is a Dell PowerEdge x86_64 system with 32 GB RAM * The host OS is Debian 6.0 * We're running Xen 4.0.1 from Debian * The guests all run Debian 6.0 * Each guest has 15 GB of storage, 512 MB RAM, and 1 GB of swap * We currently have ~40 guests running Below is some console output from a DomU that suffered this problem earlier today. You can see that the OOM killer killed Apache. And I'm guessing it killed sshd too as I couldn't connect to the guest. I couldn't find any errors in Xen's logs. Any thoughts on what might be going on here? And come September we'll have a short window in which we could alter out setup. Any suggestions for better ways of providing virtual machines? Perhaps alternatives hypervisors? Or some mechanism other than hypervisors? Cheers, Richard (Working from home: <http://pic.twitter.com/NetsgOS2>) -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Richard Lewis ISMS, Computing Goldsmiths, University of London t: +44 (0)20 7078 5134 j: ironchicken(a)jabber.earth.li @: lewisrichard s: richardjlewis http://www.richardlewis.me.uk/ -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- [ 1656.306197] rs:main Q:Reg invoked oom-killer: gfp_mask=0x201da, order=0, oom_adj=0 [ 1656.306215] rs:main Q:Reg cpuset=/ mems_allowed=0 [ 1656.306222] Pid: 1135, comm: rs:main Q:Reg Not tainted 2.6.32-5-xen-amd64 #1 [ 1656.306230] Call Trace: [ 1656.306242] [<ffffffff810b7318>] ? oom_kill_process+0x7f/0x23f [ 1656.306251] [<ffffffff810b783c>] ? __out_of_memory+0x12a/0x141 [ 1656.306259] [<ffffffff810b7993>] ? out_of_memory+0x140/0x172 [ 1656.306268] [<ffffffff810bb742>] ? __alloc_pages_nodemask+0x4ec/0x5fe [ 1656.306278] [<ffffffff810bcca9>] ? __do_page_cache_readahead+0x9b/0x1b4 [ 1656.306286] [<ffffffff810bcdde>] ? ra_submit+0x1c/0x20 [ 1656.306294] [<ffffffff810b5a66>] ? filemap_fault+0x17d/0x2f6 [ 1656.306302] [<ffffffff810cba22>] ? __do_fault+0x54/0x3c3 [ 1656.306313] [<ffffffff8130c7d1>] ? __wait_on_bit_lock+0x76/0x84 [ 1656.306323] [<ffffffff8100c3a5>] ? __raw_callee_save_xen_pud_val+0x11/0x1e [ 1656.306333] [<ffffffff810cdda8>] ? handle_mm_fault+0x3b8/0x80f [ 1656.306342] [<ffffffff8100ecf2>] ? check_events+0x12/0x20 [ 1656.306351] [<ffffffff8130fb26>] ? do_page_fault+0x2e0/0x2fc [ 1656.306360] [<ffffffff8130d9c5>] ? page_fault+0x25/0x30 [ 1656.306366] Mem-Info: [ 1656.306370] Node 0 DMA per-cpu: [ 1656.306376] CPU 0: hi: 0, btch: 1 usd: 0 [ 1656.306381] Node 0 DMA32 per-cpu: [ 1656.306388] CPU 0: hi: 186, btch: 31 usd: 75 [ 1656.306397] active_anon:55210 inactive_anon:55287 isolated_anon:1350 [ 1656.306398] active_file:10 inactive_file:11 isolated_file:26 [ 1656.306400] unevictable:0 dirty:0 writeback:171 unstable:0 [ 1656.306401] free:1180 slab_reclaimable:922 slab_unreclaimable:2187 [ 1656.306402] mapped:16 shmem:7 pagetables:7768 bounce:0 [ 1656.306422] Node 0 DMA free:2032kB min:80kB low:100kB high:120kB active_anon:6168kB inactive_anon:6312kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:14868kB mlocked:0kB dirty:0kB writeback:8kB mapped:20kB shmem:0kB slab_reclaimable:0kB slab_unreclaimable:76kB kernel_stack:16kB pagetables:292kB unstable:0kB bounce:0kB writeback_tmp:0kB pages_scanned:3 all_unreclaimable? yes [ 1656.306456] lowmem_reserve[]: 0 489 489 489 [ 1656.306467] Node 0 DMA32 free:2688kB min:2788kB low:3484kB high:4180kB active_anon:214672kB inactive_anon:214836kB active_file:40kB inactive_file:44kB unevictable:0kB isolated(anon):5400kB isolated(file):104kB present:500960kB mlocked:0kB dirty:0kB writeback:676kB mapped:44kB shmem:28kB slab_reclaimable:3688kB slab_unreclaimable:8672kB kernel_stack:1232kB pagetables:30780kB unstable:0kB bounce:0kB writeback_tmp:0kB pages_scanned:328 all_unreclaimable? yes [ 1656.306501] lowmem_reserve[]: 0 0 0 0 [ 1656.306512] Node 0 DMA: 4*4kB 1*8kB 0*16kB 1*32kB 1*64kB 1*128kB 1*256kB 1*512kB 1*1024kB 0*2048kB 0*4096kB = 2040kB [ 1656.306537] Node 0 DMA32: 232*4kB 2*8kB 1*16kB 0*32kB 1*64kB 3*128kB 1*256kB 0*512kB 1*1024kB 0*2048kB 0*4096kB = 2688kB [ 1656.306561] 8628 total pagecache pages [ 1656.306566] 8586 pages in swap cache [ 1656.306571] Swap cache stats: add 1078026, delete 1069440, find 120149/196407 [ 1656.306579] Free swap = 4kB [ 1656.306583] Total swap = 1048568kB [ 1656.308293] 131072 pages RAM [ 1656.308302] 4044 pages reserved [ 1656.308307] 22558 pages shared [ 1656.308311] 123779 pages non-shared [ 1656.308317] Out of memory: kill process 489 (apache2) score 125474 or a child [ 1656.308324] Killed process 964 (apache2)

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OT Maths Jam
by Steve Engledow 26 Jul '12

26 Jul '12

Hi folks, Would anyone be interested in a Norwich maths jam? See http://www.mathsjam.com/ for (fairly vague) details or check the twitter account (@MathsJam). tl;dr: We get together in a pub on the second-to-last tuesday of the month and be geeky. I know, it sounds like the pubmeet; but this time we be geeky about mathsy things! I reckon there ought to be enough maths geeks among the linux geeks for this to be relevant :) Steve

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Pubmeet report
by Steve Engledow 25 Jul '12

25 Jul '12

Hi all, It's been a while since a pubmeet had a write-up but I thought it was worth a go :) On a suggestion from rlp10, last night ended up being somewhat of a PGP key-signing party. All of us around the table (there were 6 of us) - plus one passer-by that I happened to know - had PGP (or rather GPG) keys so, over the course of the night, we managed to each sign eachothers keys. There was even provision of ID and encrypted emails sent to verify identity and key ownership. A fairly textbook key-signing I'd say. Additionally, we collectively managed to get a sensible mutt config together for getting GPG integrated and working. For reference, the magical invocation to make mutt understand encrypted/signed mail from Macs and Thunderbird is: message-hook '!(~g|~G)~b"^-----BEGIN\ PGP\ (SIGNED\ )?MESSAGE"' "exec check-traditional-pgp" Stick that in your .muttrc and it all works nicely. (You need a `source /path/to/muttrc.gpg`) line in there somewhere too. The path varies by distro.) Aside from the PGP-related fun, katsmeat had brought an interesting old PC that had a built-in LCD display and ran Microsoft BASIC (I don't remember what the machine actually was) and I offloaded a load of old hardware onto rlp10 \o/ The food didn't seem as good as usual. The beer did. Until next month! Steve (Stilvoid)

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SyncNorwich
by Paul Grenyer 25 Jul '12

25 Jul '12

Hi All I just wanted to make sure you guys were all aware of www.syncnorwich.com, a new group for people in Norwich interested in Technology, Startups and Agile. Out next event is some lightning talks on the 16th August and there's a Norwich lunch on the 23rd August. -- Thanks Paul Paul Grenyer e: paul.grenyer(a)gmail.com b: paulgrenyer.blogspot.com t: pjgrenyer SyncNorwich: http://www.syncnorwich.com ACCU Member: License to code: http://www.accu.org

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kernel:journal commit I/O error
by Mark Rogers 19 Jul '12

19 Jul '12

I have an ARM box which was working fine until it went to site. It's running Debian and I only have access to it via SSH (although at the moment I have someone on site who can force it to reboot). Twice today I've received the error "kernel:journal commit I/O error" to my SSH terminal, after which point the root filesystem gets unmounted and I can't do anything even though the unit is still "up". Eg: $ ls -bash: /bin/ls: No such file or directory Any ideas what would be causing this? It's an expensive SD card in these units (not a cheap no-brand) This is the unit in case anyone is interested, it's running Debian 6: http://www.newit.co.uk/shop/proddetail.php?prod=DreamPlug_N I'd also be interested to know if there's anything I can do down an SSH connection to force it to reboot, given the lack of access to the filesystem to even run "sudo" never mind "reboot". I'm guessing that sending Alt-Ctrl-Del or Alt-SysRq-B via SSH are out... -- Mark Rogers // More Solutions Ltd (Peterborough Office) // 0844 251 1450 Registered in England (0456 0902) 21 Drakes Mews, Milton Keynes, MK8 0ER

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linux apparel
by Peter Alcibiades 18 Jul '12

18 Jul '12

Hi everyone, I have three huge, I mean xxxl, linux apparel t-shirts looking for a good home. One looks like its been worn a couple of times since the brilliance of the yellow has faded slightly, the other two I don't think have been. Does anyone want them? They are fairly brilliant yellow, with a large black and white plastic penguin on the front, and on the back there is a black and white legend to the effect that this garment requires appreciation of open source freedom. Several years old. Maybe 10? Should have brought them to last Thusday, but I have not come to those for some time now. I can mail them if you let me have an address. Otherwise, its going to be the charity shop. Peter

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torcl
by richard.lee.parsons＠gmail.com 14 Jul '12

14 Jul '12

Hi all After some conversations with some Aluggers, I've thrown together a bash script for downloading torrents from the commandline. It searches isohunt, downloads your selected torrent file and kicks off the torrent client all from the warmth and safety of your favourite terminal. Perhaps it may be useful to some others on the list. https://github.com/rlp10/torcl It's pretty ugly scripting, so please forgive that. :) Richard

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Calendar GUI that has hooks for entering code when you click on a date
by Chris Green 14 Jul '12

14 Jul '12

I'm looking for a basic calendar display program that has a hook to allow me to execute a script (or other code) when I click on a date. Can anyone suggest anything like this? It can be desktop or Web. -- Chris Green

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[ALUG Announce] 3rd Monday Monthly Ipswich Social Meeting : The Mulberry Tree
by samwise 13 Jul '12

13 Jul '12

ALUG Announce Please send announcements to Announce(a)lists.alug.org.uk Unsub, change settings via http://lists.alug.org.uk/mailman/listinfo/announce ----- The monthly "Third Monday" ALUG Ipswich Social Meeting is back this week - Monday, 16th July, at 20:00: The Mulberry Tree 5 Woodbridge Road IPSWICH IP4 2EA Tel: 01473 225776 Email: mulberrytree.ips(a)btinternet.com Map/Directions URI: http://maps.google.co.uk/?q=IP4+2EA WWW: https://www.facebook.com/MULBERRYHOSPITALITY The Mulberry Tree, previously known as The Milestone Beer House, is a grade 2 listed building in the centre of Ipswich. It is located at the intersection between Woodbridge Road and the A1156, across the road from the old Odeon cinema and not far from the Regent Theatre. It re-opened on Thursday March 29th 2012 after a major refurbishment, under its original name of The Mulberry House and has already begun to regain a good reputation for its selection of beers and ales. It has a sizeable car park to the rear of the building. All are welcome, novices and experienced users. Feel free to ask for further information on the Main ALUG mailing list. After a stupidly quiet meet last time, let's see if we can drag a few more people down this month. I'll be there, and we may also have a couple of guests including, possibly, a friendly chap a few of us ALUGers met recently in the pub, who has a fair share of career stories involving the likes of Chris Curry, Clive Sinclair etc. and is currently involved in a project building unmanned aerial drones. Plus someone else may arrive armed with a MacBook who is looking to be persuaded why he should try out Linux ... Hope to see some of you there! Peter. ----- Send discussion replies to main(a)lists.alug.org.uk (Reply-To set) Unsub, change settings via http://lists.alug.org.uk/mailman/listinfo/announce

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Strange code in DNS packet unravelling - any ideas why anyone?
by Chris Green 12 Jul '12

12 Jul '12

This is again related to my Nanode (Arduino lookalike) programming, it's more of a "why on earth is it like this" sort of question than needing to know how it works. The Nanode/Arduino sits waiting for things to do which are sent as requests to its ethernet interface. It also handles DHCP, DNS, ARP and other requests in the same loop. When it gets a DNS request it checks a few things and then does the following:- // // // Check if we have a valid query for us, compare name in DNS request with our name // p=(uint8_t *)settings.Name; // set pointer to our name stored at startup if (valid) // valid set by earlier checks { for (i = NBNS_NAME+1; i < NBNS_NAME+1+32; i += 2) { c = ((buf[i] - 0x41) << 4) + (buf[i+1] - 0x41); if (*p) { if (*p!=c) { valid=0; } p++; } else { if ((c != 0) && (c != 0x20)) { valid=0; } } } } The comment at the top is mine, I *think* that's what it's doing! However I really don't understand why it's doing that strange shifting and subtracting 0x41 (yes, I know it's 'A'). It's as if the name coming in with the DNS query is two bytes per character with a strange encoding as well. I can't see anywhere else in the code where characters are spread over two bytes, and the SPI interface seems to transfer 8 bit bytes all the time to/from the ethernet hardware. I also don't understand why it's comparing only 16 characters (is it just an arbitrary local limit) and/or why the name it's receiving in the DNS request is just the hostname, not a fully qualified name. It doesn't work for lower-case characters either, the name defined for the Nanode/Arduino has to be upper case for it to respond to DNS requests. If valid is still non-zero after this it sends its IP address back to the DNS requester. Have I missed something obvious or is this really wierd? Any/all ideas very welcome. -- Chris Green

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deb/alien dependencies
by Mark Rogers 11 Jul '12

11 Jul '12

I'm trying to install hamachi [1] on Debian (arm). I want the smallest install I can get away with, but at the moment I'm getting the following dependencies: alien at autopoint bc binutils build-essential bzip2 cpp cpp-4.4 cups-bsd cups-client cups-common debhelper dpkg-dev fakeroot g++ g++-4.4 gcc gcc-4.4 gettext gettext-base git html2text intltool-debian libalgorithm-diff-perl libalgorithm-diff-xs-perl libalgorithm-merge-perl libc-dev-bin libc6-dev libcurl3-gnutls libdpkg-perl libelf1 liberror-perl libgmp3c2 liblua5.1-0 libmail-sendmail-perl libmpfr4 libnspr4-0d libnss3-1d librpm1 librpmbuild1 librpmio1 libstdc++6-4.4-dev libsys-hostname-long-perl libtimedate-perl libunistring0 linux-libc-dev lsb-core lsb-release m4 make manpages-dev ncurses-term patch pax po-debconf rpm rpm-common rpm2cpio time It installs and runs OK but I don't want all that stuff on my box afterwards! Seeing alien in the list makes me conclude that this is a repackaged rpm and maybe that's what's causing the problem. However if I try to "apt-get remove alien" afterwards, hamachi gets removed. What are my options to work around this? Unfortunately Hamachi is not free and therefore I don't have access to the source. [1] https://secure.logmein.com/labs/ -- Mark Rogers // More Solutions Ltd (Peterborough Office) // 0844 251 1450 Registered in England (0456 0902) 21 Drakes Mews, Milton Keynes, MK8 0ER

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Capturing Olympic torch relay footage from BBC website
by Mark Rogers 09 Jul '12

09 Jul '12

Does anyone have any idea how to capture the torch relay footage from the BBC website? I expected get-iplayer to do the job but it can't find the stream if I just paste the URL in. Specific example: http://www.bbc.co.uk/torchrelay/day46 (Afternoon section) Mark Rogers

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FTP server mirroring (push not pull)
by Mark Rogers 06 Jul '12

06 Jul '12

I have a system which uploads data to my FTP server periodically. I need to upload any files that arrive to a second (and possibly third) FTP server. The points that make it not fit a traditional mirroring is that (a) my FTP server needs to push the files out to the other server(s) rather than have them pull the files in, and (b) the data needs to be synchronised as fast as possible after it arrives (the files are alarm logs amongst other things). So an hourly or daily cronjob won't suffice. Although I have control over my own FTP server, I can't make any assumptions about the third party servers in terms of their O/S, functionality, FTP server software, etc. Any suggestions for the best place to start with this? -- Mark Rogers // More Solutions Ltd (Peterborough Office) // 0844 251 1450 Registered in England (0456 0902) 21 Drakes Mews, Milton Keynes, MK8 0ER

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Barclays Online Banking
by Ted.Harding＠wlandres.net 05 Jul '12

05 Jul '12

Greetings all! Anyone out there who banks with Barclays and is having problems accessing Online Banking with Linux? I last logged in 6 days ago with no problems. Today, when I try to access it, no login page comes up -- it just hangs forever. So I can't even try to get started! I'm using (an admittedly slightly elderly) Iceweasel 2.0.0.19 of 2006 on a Debian Etch 2.6.18 last updated Feb 2010. Any suggestions most welcome! Best wishes to all, Ted. ------------------------------------------------- E-Mail: (Ted Harding) <Ted.Harding(a)wlandres.net> Date: 12-Jun-2012 Time: 19:00:45 This message was sent by XFMail -------------------------------------------------

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Storing data samples with low overheads
by Mark Rogers 04 Jul '12

04 Jul '12

I'm writing an application to run on small ARM units. It collects data from various sources at varying frequencies (up to once per second) and needs to store them. The number of discrete values will vary but we're running tests on around 200 data points dropping the data into MySQL. By "varying frequencies" what I mean is that some items will be read every second, others less frequently (say once every 30mins), so I need a data structure that will cope with that but my tests are currently on the worst-case of storing everything every second (or trying to!) One option is to have a table per item, comprising little more than timestamp and value. Our tests so far have taken 2-5s to store 200 samples this way. We're looking at other ways (eg one table for all samples, storing an item id, timestamp and value). However I can't help think that MySQL is overkill and an overhead we could do without. So, does anyone have any suggestions? We could build our own data storage system - the applications I've seen before that do this would probably have a single binary file per day/week/month of data for any single item, storing a single timestamp (marking the start of the file) and sample period, followed by 4 bytes per sample at the appropriate offset into the file from there; reading or writing just becomes a case of working out which file to look at and the offset into that file. But I'd rather not go quite so low-level if I can avoid it. -- Mark Rogers // More Solutions Ltd (Peterborough Office) // 0844 251 1450 Registered in England (0456 0902) 21 Drakes Mews, Milton Keynes, MK8 0ER

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