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10369 discussions

Re: [ALUG] Machine won't boot after re-install
by Jim Rippon 04 Apr '12

04 Apr '12

Re-posting as my reply wasn't to the group at large last time. Grub2 introduces further complications, and I'd have to refer you to your distribution's documentation on the subject, or a search for "grub2 configuration" - wayne's suggestion to not overwrite /boot with your restore is important. Jim > Hello Jim, > > I'm writing this from a webmail account so apologies for not snipping > anything. > > I've fixed the fstab file but it's still doing it. I *think* the > problem > is the > grub configuration. Is there any way I can fix that without another > re-install? I have to say I'm getting quite adept at that now though! > Hi Chris, Depending on how your installer has managed the disk partitioning, you will either find the grub configuration in /boot/grub on your root partition, or on its own boot partition (check in the afore-mentioned fstab file for an entry mounted at "/boot"). In here you'll have a grub folder containing menu.lst This config file drives your grub bootloader, its possible that the commands in here are pointing at a uuid or partition thats incorrect - make a note of all the partitions you've installed to, and ensure they appear something like the following for your linux boot entry: title Arch Linux root (hd0,0) kernel /vmlinuz-linux root=/dev/sda3 ro initrd /initramfs-linux.img The important lines are: * root (hd0,0) -> pointing at the first disk, and first partition as the location for the boot files (the grub files and kernels where you found this config file normally - either your root partition or a seperate boot partition) * kernel /vmlinuz-linux root=/dev/sda3 ro -> this is the line which starts the kernel from your boot partition and tells it where to mount its root filesystem (in my case here, my system has created an initial ramdisk and its root partition is /dev/sda3 - partition 3 on my first SATA disk). Hope this helps point you the right direction. Jim > > I do have a liveCD - I run Mandriva 2011 - but I want to make sure I > don't > screw up anything else in trying to fix this problem. > > One other source of rogue files is the /run folder as that has a > couple of > files in /run/udev/rules.d/99-root.rules and 99-resume-link.rules but > even > deleting those had no effect so that's when I went looking for other > causes. I've examined the .tgz backup files under Windows (the > machine > dual boots) and that's where I've just discovered the grub files. > > Regards > Chris

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Machine won't boot after re-install
by cdw_alug＠the-walker-household.co.uk 04 Apr '12

04 Apr '12

I did a backup of my machine using tar commands and have then resized the various partitions. I reinstalled the OS from the original DVD and then started to restore the original files, extracting them from the various tar files - I wrote a separate tar file for each of the folders in starting from / such as '/opt-backup.tgz' I took notice of what Brett said last week about not doing a backup of /dev so that should remain untouched from the install. But now having restored everything, it comes up with the message 'No root device "block:/dev/disk/by-uuid/<disk-id here>" found and then 'resume device /dev/disk/by-uuid<another disk-id>' If I start again with the install, which of the various tar files should I *not* restore to avoid this problem ad infinitum? TIA.

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2600 meeting at 18:00 on Friday the 6th April.
by Viperfang 03 Apr '12

03 Apr '12

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

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Processing power and bandwidth needed for streaming internet radio
by Chris Green 02 Apr '12

02 Apr '12

I'm confused! (so what's new?) My Acer Aspire laptop runs the little dedicated internet radio application I found quite recently with no problems at all when I run it at home. There it has an ADSL connection with something between 3Mb/s and 4Mb/s. However when I try it here (in France) using the WiFi service here it's completely useless, i.e. it produces about one second in five of actual sound. The bandwidth here is quite good though, the BBC iPlayer bandwidth check (which should be vaguely relevant as I'm trying to listen to the BBC) tells me:- Download speed: 1778 kbps Streaming speed 1: 1512 kbps Streaming speed 2: 1958 kbps Streaming speed 3: 1122 kbps Which the BBC says isn't quite enough for HD TV (!) but should manage anything else - all I want is a single radio channel! Does a lower connection speed require a faster processor to keep up or should I be looking somewhere else for what's causing the totally broken up internet radio here? -- Chris Green

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Really odd USB error/failure with Genius mouse
by Chris Green 02 Apr '12

02 Apr '12

I'm not really expecting a solution to this, just ranting/reporting an oddity. It confirms my general distrust/hatred of USB in general! :-) I have a little Acer Aspire netbook that I use (as I am now) when away from home, it runs xubuntu 11.10 (though I'm fairly certain I saw the same problem with previous versions of xubuntu). I use a Genius/Kye Traveller 350 mouse with it rather than the horrible touchpad. This works beautifully as it's actually a trackball rather than a mouse and has a scrollwheel and a fourth button that I have programmed as a double click of button one - bliss! :-) However after a random amount of time the Genius mouse stops working, since this is quite a long time (like hours rather than minutes) it doesn't often worry me too much as I don't spend hours on my laptop. Tonight though I decided to have a play and see if I could work out why it stops working (as the netbook had been left turned on and the mouse had, as usual, stopped working). I have the mouse plugged into the left hand side of the netbook where there are two USB ports as I usually use it left handed (even though I'm actually right handed). Since it had died just now I unplugged it and plugged it back in a couple of times, nothing, dmesg/syslog shows nothing, it's as if the mouse doesn't exist. If I reboot though it will work with no problem. Then I tried plugging it into the USB port on the RHS of the netbbok, and it works! It's still working. I can plug/unplug it repeatedly and it works every time. If I plug it in to the LHS ports there's still nothing happening though. Other devices (e.g. memory sticks) plugged into the LHS USB ports work perfectly though. It's just the mouse that won't work in the LHS ports (until I reboot!). Wierd! I think USB is a creation of arcane beings. -- Chris Green

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Directories to exclude on a backup
by Chris Walker 01 Apr '12

01 Apr '12

I'm about to backup my system as I want to resize the sda1 partition and I didn't think it was possible to do that with an existing system. So I looked online and found a Ubuntu guide to it which suggests excluding the following directories :- /proc /lost+found /mnt /sys/ I intend to backup /home separately so I will also exclude that but is the list reasonable or are there others I should also exclude? TIA

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2600 meeting at 18:00 on Friday the 2nd March.
by Viperfang 28 Mar '12

28 Mar '12

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

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Re: [ALUG] Best mobile phone for Linux nowadays?
by Chris Green 27 Mar '12

27 Mar '12

On Sun, Mar 25, 2012 at 12:40:16PM +0100, Tim Green wrote: > > Chris Green <cl(a)isbd.net> wrote: > > >My wife's Palm Treo has died (after bing dropped for the umpteenth time) > >so she needs a replacement. > > > >The fundamental requirement is a phone which will synchronise contacts and > >calendar with Evolution or Thunderbird/Lightning. > > > >So what's the best way to go nowadays? > > > >We'd prefer direct phone <--> desktop synchonization but I suppose it's > >not absolutely vital. However I'm happy enough to install a sync server > >of some sort (though my experience with Funambol was not an entirely > >happy one when I was trying the same with my Nokia E71 a year or so > >ago). > > > These days all the cool kids sync with the cloud (e.g. with Android its Google). Is that an option for you? > Sort of, that's what I meant by "We'd prefer direct phone <--> desktop synchonization but I suppose it's not absolutely vital. We defnitely *do* need it to be easy/transparent to keep Evolution (or Lightning) calendar in sync with phone calendar. If this goes via the cloud then so be it but the cloud bit will only be used as a sort of server. So to have to explicitly synchronize Evolution <-> cloud and then separately synchronize phone <-> cloud is out. On the other hand it it can be made to just happen when changing things at either end then that's fine. Something that *relies* on having an internet connection all the time to work is out as we are often out of reliable mobile phone network coverage. At home the mobile coverage is often flakey and when we're on the boat in France it may be non-existent at times. -- Chris Green

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Wanted - command line program for listening to BBC radio streams
by Chris Green 27 Mar '12

27 Mar '12

I'm looking for a command line program to listen to BBC radio live streams. I'm a bit of a newbie with trying to do this and I'm a bit confused by the fact that all of the URLs I can find for 'streaming' are actually playlists. But anyway, be that as it may, I have tried a couple of programs to listen to the .asx streams that seem to be the most readily available BBC streams with mostly rather poor results:- mpg321 - doesn't seem to recognise URLs at all though the man page says it should. mpg123 - recognises some URLs (in particular .pls ones) but doesn't appear to understand .asx. mplayer - this manages to play .asx URLs but it's really a movie player and thus drags in far more bits and pieces than I want, playback is still choppy. How much processor power and/or bandwidth is required to play a basic radio stream? -- Chris Green

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Mail Server
by Paul Grenyer 27 Mar '12

27 Mar '12

Hi all I want to create an email server so that I can send and receive email for a number of my domains. I've tried using postfix, but it's a pig to setup and it appears I need to have a user account on the server for every email address and I can't restrict one user to only one domain. e.g. if I create a user called paul and I have two domains, I get paul@domain1 and paul@domain2. Of course this could be my misunderstanding. So, I would like recommendations for a mailserver to run on ubuntu. Ideally I'd like it to be: 1. Easy to setup 2. Not require a user to be created for each email address. 3. Be able to create email addresses for individual domains 4. Web interface 5. Work with mailman 6. Support pop/imap 7. Support email forwarding. Any suggestions? -- Thanks Paul Paul Grenyer e: paul.grenyer(a)gmail.com b: paulgrenyer.blogspot.com t: pjgrenyer

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26 Mar '12

Hi all, I'm having problems logging in. Initial login takes an age (~1 minute). Sudo in a terminal takes also take an age, but if I log out and log back in again, I get an immediate login. I think I've had a problem like this before where I had set up something wrong, so that the thing that was handling the login was trying to connect to a non-existant windows server to verify the login, waiting for a time-out, then handling the login itself. On subsequent logins, it's like it knows it's timed out, and doesn't bother trying. This is on my server, and it should be responsible for it's own log-ins. It's running dnsmasq, and is a samba server. I've set samba so that it says it is the authoritative nameserver. Any idea what's going wrong, or what I can look at to work out what's going wrong. There's nothing obvious to me in the log file viewer, or Dmesg. Any other log files to look at or config files to tweak? Any way to view what the login process is doing?? Ubuntu server 10.04.4 LTS Any help gratefully received. Steve

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How to decide which printer driver to use in CUPS?
by Chris Green 26 Mar '12

26 Mar '12

Does anyone else suffer from this dilemma? Whenever I install my HP Laserjet 1320 printer I wonder which of about a dozen or so alternatives that CUPS offers to use. For HP 1320 I see:- HP Laserjet 1320 - CUPS+Gutenprint v5.2.7 (en) HP Laserjet 1320 - CUPS+Gutenprint v5.2.7 Simplified (en) HP Laserjet 1320 Foomatic/Postscript (en) HP Laserjet 1320 Foomatic/pxlmono (recommended) (en) HP Laserjet 1320 hpijs, 3.11.7 (en) HP Laserjet 1320 hpijs pcl3, 3.11.7 (en) HP Laserjet 1320 pcl3, hpcups 3.11.7 (en) HP Laserjet 1320 series Postscript (recommended) (en) HP Laserjet 1320 series Postscript (recommended) (en) HP Laserjet 1320 series Postscript (recommended) (en) HP Laserjet 1320, hpcups 3.11.7 (en) There's no 'help' to click on to give any guidance, I *guess* I can't use the Postscript ones as my printer doesn't have Postscript (and, yes there really are three apparently identical Postscript entries). But how do I decide between that odd mix of pcl3, hpijs and hpcups? -- Chris Green

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Best mobile phone for Linux nowadays?
by Chris Green 25 Mar '12

25 Mar '12

My wife's Palm Treo has died (after bing dropped for the umpteenth time) so she needs a replacement. The fundamental requirement is a phone which will synchronise contacts and calendar with Evolution or Thunderbird/Lightning. So what's the best way to go nowadays? We'd prefer direct phone <--> desktop synchonization but I suppose it's not absolutely vital. However I'm happy enough to install a sync server of some sort (though my experience with Funambol was not an entirely happy one when I was trying the same with my Nokia E71 a year or so ago). -- Chris Green

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Re: [ALUG] Mail Server
by Stuart Bailey 25 Mar '12

25 Mar '12

Hi Paul, I think postfix is still tour best bet. You can authenticate users against MySQL, ldap or sasldb, so you don't need a linux account for each user. You email addresses can be handled the virtual domains, so Paul@anydomain can be configure to go to one account for Paul, or you can have separate accounts for Paul. Any combination can be configured. Stuart Bailey BSc (hons) CEng CITP MBCS LinuSoft (Managing Director) Linux Specialist & Software Developer ~~~~~~~~~~~~~~~~~~~~~~~ Phone: (0845) 658 3563 Direct: +44 (0) 1953 878162 Fax: +44 (0) 1603 858583 ~~~~~~~~~~~~~~~~~~~~~~~ http://www.linusoft.co.uk ----- Reply message ----- From: "Paul Grenyer" <paul.grenyer(a)gmail.com> To: "ALUG ML" <main(a)lists.alug.org.uk>, "accu-general" <accu-general(a)accu.org> Subject: [ALUG] Mail Server Date: Sat, Mar 24, 2012 20:57 Hi all I want to create an email server so that I can send and receive email for a number of my domains. I've tried using postfix, but it's a pig to setup and it appears I need to have a user account on the server for every email address and I can't restrict one user to only one domain. e.g. if I create a user called paul and I have two domains, I get paul@domain1 and paul@domain2. Of course this could be my misunderstanding. So, I would like recommendations for a mailserver to run on ubuntu. Ideally I'd like it to be: 1. Easy to setup 2. Not require a user to be created for each email address. 3. Be able to create email addresses for individual domains 4. Web interface 5. Work with mailman 6. Support pop/imap 7. Support email forwarding. Any suggestions? -- Thanks Paul Paul Grenyer e: paul.grenyer(a)gmail.com b: paulgrenyer.blogspot.com t: pjgrenyer _______________________________________________ main(a)lists.alug.org.uk http://www.alug.org.uk/ http://lists.alug.org.uk/mailman/listinfo/main Unsubscribe? See message headers or the web site above! __________ Information from ESET Mail Security, version of virus signature database 6995 (20120324) __________ The message was checked by ESET Mail Security. http://www.eset.com

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Mangled pemnissions in a directory
by Ted.Harding＠wlandres.net 24 Mar '12

24 Mar '12

Greetings all! I have a wierdly mangled directory ("funny-dir" for present purposes). This may have occurred during a machine crash (I'm running this in a VirtualBox machine hosted on Windows and I recall that a few days ago the Windows host crashed). Basically: from the parent directory, if I do 'ls -l' I see: drw-r--r-- 2 ted ted 4096 2012-03-11 18:53 funny-dir and that looks fine. But if I then do 'ls -la funny-dir' I see a lot of stuff all looking like: ?--------- ? ? ? ? ? funny-dir/. ?--------- ? ? ? ? ? funny-dir/.. ?--------- ? ? ? ? ? funny-dir/file1.pdf ?--------- ? ? ? ? ? funny-dir/file2.pdf [and so on] Note that the "/." and "." both get the "?" attributes when viewed using 'ls -la funny-dir', as compared with the normal results viewed using ls -l' as above. Finally, if I try 'cd funny-dir' I get: bash: cd: funny-dir: Permission denied However, if I 'su' to root, 'ls -la' gives: drw-r--r-- 2 ted ted 4096 2012-03-11 18:53 funny-dir/. drwxr-xr-x 4 ted ted 4096 2012-03-24 21:07 funny-dur/.. -rw-r--r-- 1 ted ted 4766 2012-03-10 16:18 funny-dir/file1.pdf -rw-r--r-- 1 ted ted 4738 2012-03-10 16:19 funny-dir/file2.pdf [and so on] which is all as it should be! I can also, as root, 'cd funny-dir', and again things look normal from inside funny-dir. Can anyone say (a) What's going on? (b) How best to fix it? This is the first time ever thar I've seen this sort of thing happen. I'd like to be able to fix it directly, since the files were put in there by saving them out of several emails, each with several attached files with daft ("Windows" style) names which I had to change (every one); there are over 40 files, and it took ages!! With thanks, and best wishes to all, Ted. ------------------------------------------------- E-Mail: (Ted Harding) <Ted.Harding(a)wlandres.net> Date: 24-Mar-2012 Time: 21:33:56 This message was sent by XFMail -------------------------------------------------

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Government ePetition
by Montmorency 21 Mar '12

21 Mar '12

Don't think too many ALUGers would disagree with this one. e-Petition to put Alan Turing on the next £10 note: http://epetitions.direct.gov.uk/petitions/31659 Montmorency montmorency(a)ukfsn.org bellphegore(a)nerdshack.com

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Java not installed?
by Chris Walker 21 Mar '12

21 Mar '12

I'm trying to install this - http://sourceforge.net/p/necessitas/wiki/How%20to%20install%20Necessitas%20… but it keeps telling me that I need a java compiler. I've installed java-1.6.0-openjdk but I'm still getting the same message from Necessitas. I've tried issuing the urpmi command to install openjdk and it tells me :- No package named openjdk The following packages contain openjdk: java-1.6.0-openjdk, java-1.6.0-openjdk-demo, java-1.6.0-openjdk-devel, java-1.6.0-openjdk-javadoc, ... My system is Mandriva 2011.0 64bit. Any ideas how I can overcome the error message please?

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Scanners
by Bev Nicolson 21 Mar '12

21 Mar '12

Have scanner won't scan. We've been there before but not with Simple Scan. It knows my AGFA Snap Scan is there but says it's unable to connect. It is plugged in! I've tried gksudo simplescan (was that right?) and nothing happened. Is it another case of having to install VueScan?* And if it is, can someone kindly take me through how to install it? Many thanks. Bev. (11.04.) *That's what I had to do with my last computer to get it to work.

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Really strange automount symptoms
by Chris Green 20 Mar '12

20 Mar '12

I have been trying to diganose/fix this automount problem for quite a while. Automount of CDs, DVDs and USB sticks works fine on two of my xubuntu 11.10 systems but not on my desktop system. While trying to diagnose this I have found that it makes a difference using a remote display! If I run thunar on my system called 'test' where it works I see:- thunar-volman: Unsupported USB device type. thunar-volman: Unsupported USB device type. thunar-volman: Unknown block device type. ... and the USB stick automounts fine. If I do exactly the same except by a remote ssh connection to 'test' from my desktop system 'chris', I see:- thunar-volman: Unsupported USB device type. thunar-volman: Unsupported USB device type. thunar-volman: Unknown block device type. thunar-volman: Could not detect the volume corresponding to the device. ... and the USB stick *doesn't* automount. When I run thunar locally on my desktop system I see the same output (and failure to mount) that I see when running via ssh on 'test'. What on earth is going one? -- Chris Green

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TeamCity & Jenkins behind Apache2 Proxy
by Paul Grenyer 19 Mar '12

19 Mar '12

Hi All (Please excuse the cross posting) I've Jenkins and TeamCity running on two separate VMs within my home network. I have another (physical) box running, among other things, Apache 2 (on Ubuntu server) and I have port 80 forwarded from my router to it. I've configured a number of virtual hosts on Apache, which work fine, and have proxies to two other web applications (subsonic & Nexus) running on Tomcat on the same box. What I want to do is add proxies for Jenkins and Tomcat. This is my configuration: <VirtualHost *:80> ... ProxyRequests Off ProxyPreserveHost On <Proxy *> Order allow,deny Allow from all </Proxy> ProxyPass /subsonic/ http://localhost:8080/subsonic/ ProxyPassReverse /subsonic/ http://localhost:8080/subsonic/ ProxyPass /nexus/ http://localhost:8080/nexus/ ProxyPassReverse /nexus/ http://localhost:8080/nexus/ ProxyPass /teamcity/ http://192.168.1.x1:8080/ ProxyPassReverse /teamcity/ http://192.168.1.x1:8080/ ProxyPass /jenkins/ http://192.168.1.15/ ProxyPassReverse /jenkins/ http://192.168.1.x2/ </VirtualHost> I think the Apache 2 configuration is fine and that the problems reside in the TeamCity and Jenkins configurations. I access them like this: http://<mydomain>/teamcity/ http://<mydomain>/jenkins/ In the case of TeamCity, it tries to redirect me to login.html, but looses the /teamcity/ part from the URL. In the case of Jenkins, the first obvious issue is that the CSS isn't referenced properly and some of the links don't work. I've done the obvious stuff like update the server URL for both TeamCity and Jenkins (just like I had to with Nexus). I've restarted everything, even the boxes/VMs. And Iv'e googled. I'm still stuck. Does anyone know what I'm doing wrong? -- Thanks Paul Paul Grenyer e: paul.grenyer(a)gmail.com b: paulgrenyer.blogspot.com t: pjgrenyer

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Backup Trigger Method
by Paul Grenyer 18 Mar '12

18 Mar '12

Hi all I want to setup some regular backups on my Ubuntu server box. I have done this before, but it was a while ago and I don't remember how I did it. I seem to remember dropping some scripts into directories the contents of which are executed at a particular interval. However, i can't find these directories on the server i did it on and google isn't helping, What's the best way to schedule backups? -- Thanks Paul Paul Grenyer e: paul.grenyer(a)gmail.com b: paulgrenyer.blogspot.com t: pjgrenyer

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How do USB drives get automounted? (mine don't and I'm trying to work out why)
by Chris Green 18 Mar '12

18 Mar '12

I have three xubuntu 11.10 systems running here, one is a 32-bit laptop and two are 64-bit desktop machines. USB drives plugged into the laptop and one of the dekstop machines get automounted correctly but on the other desktop machine although the USB drive is recognised (appears in dmesg as it should) it doesn't get automounted. So how can I diagnose what's wrong or missing on the desktop machine where the automounting doesn't work? I think it's *possible* that I have removed something necessary and/or misconfigured something as this machine is quite heavily customised. As I have a working machine and a non-working one I may be able to compare things between the two machines to see what is wrong but I need to know the sort of places I should be looking. What processes and packages are involved in automounting a USB drive? As I said it appears to be recognised correctly by the kernel, messages in dmesg and syslog are the same on both the system where it's not automounted and the system where it is. After the kernel has recognised the USB device as a mass storage device what then mounts it automatically and (if configured to do so, which it is) pops up thunar? Any/all help would be most welcome as this problem is getting really annoying! -- Chris Green

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[ALUG Announce] 3rd Monday Monthly Ipswich Social Meeting : McGintys, Northgate Street
by samwise 17 Mar '12

17 Mar '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 Monday, 19th March, at 20:00: P J McGinty & Sons 15 Northgate Street Ipswich Suffolk IP1 3BY Tel: 01473 251 515 Map/Directions URI: http://maps.google.co.uk/?q=IP1+3BY WWW: http://www.pjmcgintys.co.uk/ McGintys pub is in the centre of Ipswich. It's directly opposite the town's central library and has a reputation for good Irish beer. We're usually to be found in the lowest section of the bar, near the library entrance to the pub. All are welcome, novices and experienced users. Feel free to ask for further information on the Main ALUG mailing list. *** I'll be there to start with but due to a rather big family medical issue, I may not be able to stick around for more than an hour. Will have to see on Monday. *** 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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Determining "my" LAN IP
by Mark Rogers 16 Mar '12

16 Mar '12

What's the best way (programatically) to determine the local IP which would be used to make a connection to a specific destination? By way of example, the following works: $ tracepath -n 192.168.251.132 1: 192.168.251.140 3.816ms pmtu 1500 1: ... $ tracepath -n 10.0.0.1 1: 10.0.0.140 1.455ms pmtu 1500 1: ... In other words the PC I ran it on has several IP addresses (and several interfaces), but from the above I can determine that for destination 192.168.251.132 by source IP will be 192.168.251.140, but for destination 10.0.0.1 it will be 10.0.0.140. However this is quite slow and messy, and there is surely a better way! Mark Rogers -- 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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Any UDP comms experts here?
by Mark Rogers 16 Mar '12

16 Mar '12

I have a device I need to talk to via UDP from within PHP (although it feels like my problem here is a Linux one not a PHP one as everything is being done at the socket level anyway). I am sending a request to an Ethernet module in a PLC, and if I get the addressing wrong in my request then I get an error response back from the PLC as expected (by which I mean a 22 byte message sent via UDP containing the relevant error code) - I see this in my PHP code and in a Windows (Winsock-based) app I have that lets me send test queries and see the responses. However, when I get my addressing correct, whilst the Windows app gives me the response associated with the request I made, in my PHP/Linux code I just get no response (my code hangs up waiting). The PHP code I'm struggling with is: // Create a socket $socket = socket_create(AF_INET, SOCK_DGRAM, SOL_UDP); // Build the message $msg = hex2str('80 00 02 00 01 00 00 11 00 00 05 01'); // Send the message socket_sendto($socket, $msg, strlen($msg), 0, '192.168.251.132', '9600'); // Get the response - this line never returns socket_recvfrom($socket, &$buf, /*Max response length*/250, /*Flags*/0, &$ip, &$port); I would guess that the Ethernet module in the PLC either responds immediately with a response to tell me I have the address wrong, or else has to go off and collect some data before sending it back, although the time this takes is milliseconds. If I set Flags to MSG_DONTWAIT the code no longer hangs; it just returns no characters, even if I put a delay of a couple of seconds before the function call. I'm pretty sure that the key to the solution lies in getting the flags right but there I'm stumped due to lack of knowledge (and everywhere I can find sample code the above works fine). The list of possible flags is in the PHP docs[1] but I think a fuller list would be those listed in "man 2 recv" Any suggestions? [1]http://www.php.net/manual/en/function.socket-recvfrom.php -- 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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