December 2012 - luv-main

Migrating from hdd to ssd drive
by Daniel Dalton 18 Dec '12

18 Dec '12

Hi everyone, Today I updated my laptop to use an ssd drive. I am using a Samsung 830 series (128 Gb) drive. I've got most things working nicely, but I had a few questions that others who have already done this may be able to assist with: 1. Hibernate has seemed to stop working for me ever since I installed the ssd. I'm fairly sure it worked with the old hard drive, but now if I pm-hibernate, and turn back on the machine, it is just equivalent of shutting down and booting. i.e. my session is not resumed, and I am asked to log in. I have a swap partition, output of free -m is: daniel@Vostro-3350:/tmp$ free -m total used free shared buffers cached Mem: 3947 659 3287 0 35 346 -/+ buffers/cache: 278 3669 Swap: 6143 0 6143 2. What tweaks do people use to prolong ssd life and also improve performance? Currently I have an fstab which looks like this: # /etc/fstab: static file system information. # # Use 'blkid' to print the universally unique identifier for a # device; this may be used with UUID= as a more robust way to name devices # that works even if disks are added and removed. See fstab(5). # # <file system> <mount point> <type> <options> <dump> <pass> # / was on /dev/sda2 during installation UUID=ed09c67d-bd34-42be-8f3b-3dfb567ea764 / ext4 errors=remount-ro,discard,noatime 0 0 UUID=9db7ef9e-5298-4400-8b26-cdf9d6ec4168 /home ext4 defaults,discard,noatime 0 0 # swap was on /dev/sda6 during installation UUID=3df92924-3bd3-4292-a635-a78e9e36d9c8 none swap sw 0 0 tmpfs /tmp tmpfs defaults,noatime,mode=1777 0 0 (obviously partition table has changed a bit since I moved from a dual booting system on the hdd to just ubuntu on ssd) I've also made a symbolic link from /var/log to /tmp/ which should apparently help reduce writing to the ssd. (apparently the last line of the fstab means /tmp is stored in ram) I've also added this in /etc/default/grub, and ran update-grub: GRUB_CMDLINE_LINUX="elevator=noop" Is there anything else I should do? 3. My last question: I here alignment is important to ensure best performance and again help prolong the life of the ssd. >From what I read using a multiple of 512 for the first block can achieve this. I attempted to do this with fdisk, but to be honest, was not quite sure what I was doing. (I actually just cp -ax /from/hdd* /to/path/ssd for my ubuntu installation, so didn't use the ubuntu install cd to install on the ssd. (so obviously created all partitions manually). Here is my fdisk output: daniel@Vostro-3350:/tmp$ sudo fdisk -l /dev/sda Disk /dev/sda: 128.0 GB, 128035676160 bytes 255 heads, 63 sectors/track, 15566 cylinders, total 250069680 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x3f5f6184 Device Boot Start End Blocks Id System /dev/sda1 * 2048 31459327 15728640 83 Linux /dev/sda2 31459328 44042239 6291456 83 Linux /dev/sda3 44042240 250069679 103013720 83 Linux Are these partitions aligned? If not how can I repair this, (hopefully not by re-installing!) I'm running ubuntu 12.10 as well. Thanks in advance for any help, Dan

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Re: Apache reverse proxy on Ubuntu
by Theng Ung 17 Dec '12

17 Dec '12

Hi Daniel, Yes, I am aware of port forwarding. This website involve with online transaction so I believe the purpose is to hide the actual web server itself as well as resolving issue that experience previously with port forwarding with online transaction. Regards, Theng On 17/12/12 17:33, Theng Ung wrote: I am not sure what you are trying to achieve with reverse proxy and I don't think that is what it is for. If you want to make 192.168.1.20 viewable to outside world, you should really be using port forwarding. I suggest you lookup how to setup port forwarding on Linux. Cheers Daniel. > > > > > > > > >_______________________________________________ luv-main mailing list luv-main(a)luv.asn.au http://lists.luv.asn.au/listinfo/luv-main

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Apache reverse proxy on Ubuntu
by Theng Ung 17 Dec '12

17 Dec '12

Hi, Just want to ask anyone that know how Apache reverse proxy work. I am trying to understand a setup for a friend. web server running on windows server with internal ip 192.168.1.20. DNS record for www.abcd.com.au with 203.x.x.10. Linux box (Ubuntu) is setup as reverse proxy server with external eth0 with ip 203.x.x.10 and internal eth1 ip 192.168.1.10. Below is the config from /etc/apache2/site-enable <VirtualHost *> ServerName mail.abcd.com.au ServerAlias *.abcd.com.au RewriteEngine on RewriteRule /.* http://www.abcd.com.au/ [R] </VirtualHost> Base on the above config, I unable to understand how Linux able to redirect web client to the internal web server or from webserver back to client browser. /etc/hosts have www.abcd.com.au point to 192.168.1.20. Regards, Theng

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Re: Bridge mode ADSL modems
by Andy Dean 17 Dec '12

17 Dec '12

On 17 Dec 2012, at 07:54, Mark Dods <madods(a)optusnet.com.au> wrote: > On 17/12/2012 6:23 PM, Andy Dean wrote: >> Hi >> >> A vigor 120 would work although ADSL speeds wouldn't be as good as your current modem. >> > > Why wouldn't the speeds be as good? Is the Vigor unit pessimistic about how much loss it will tolerate before switching to a lower rate? > >> Deano >> >> sent from my Android >> >> On 17 Dec 2012 07:21, "Mark Dods" <madods(a)optusnet.com.au> wrote: >> I have a Ubuntu server running pppoe through a D-Link DSL-502T in >> Annexe-M and bridge mode. The DSL 502T seems to have become a bit flakey >> in that seems to require restarting every week or so, whereas it used to >> run for months without being touched. >> >> So I'm looking for a drop-in replacement, but everything currently >> available seems to have wireless (which I don't want) and/or I can't >> confirm they support bridging and Annexe-M. >> >> Can anyone suggest a current model modem I could drop in? >> >> -- >> Regards, >> >> Mark Dods, VK3ZR madods(a)optusnet.com.au >> QF22NE >> >> _______________________________________________ >> luv-main mailing list >> luv-main(a)luv.asn.au >> http://lists.luv.asn.au/listinfo/luv-main > > > -- > Regards, > > Mark Dods, VK3ZR madods(a)optusnet.com.au > QF22NE Hi, the speeds have never been as good with vigour's in my experience due to the chips they use. The other possibility would be a billion 7800 I believe this will work as a modem but comes with a better chipset and is well support by billion. Not the cheapest of routers though. thanks Deano

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Linux Australia Name Change?
by Lev Lafayette 17 Dec '12

17 Dec '12

Hi LUVers, Posted here because it is related to Linux and LUV. Many of you may have noticed that Linux Australia is voting for a name change. https://www.linux.org.au/membership/index.php?page=view-election&id=18 This is one of three votes When first vote is done, if the winner is not "Leave Linux Australia's name unchanged", Linux Australia will attempt to reserve the top three names with the NSW Department of Fair Trading. They will then hold a second run-off vote between these top three names. This second vote will once again be optional preferential, meaning you can rank none, some or all of the suggested names in your order of preference. If the result of the second vote is to change our name, the council will contact the NSW Department of Fair Trading and register the winning name as a Registered Business Name. They will then call a Special General Meeting to officially change the name of Linux Australia, which requires 75% approval at the SGM. At the last committee meeting LUV decided not to adopt an official position on the subject. On a personal note, I voted "Leave Linux Australia's name unchanged". The existing name has served the organisation well and I wasn't impressed with the alternatives. Please note that this discussion is *only* about Linux Australia's name. It does not have any bearing on subjects such as whether LUV (or other LUGs) should dis-incorporate and become a committee of Linux Australia (or whatever), like SLUG has done. Although a name change does *imply* a change of focus of the organisation, that it will become "Free, Libre, Open Source" technology organisation, rather than a Linux organisation. All the best, -- Lev Lafayette, mobile: 0432 255 208 http://www.ietf.org/rfc/rfc1855.txt

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BTRFS snapshots etc
by Russell Coker 17 Dec '12

17 Dec '12

http://etbe.coker.com.au/2012/12/17/using-btrfs/ I've written my own scripts to manage snapshot backups on BTRFS and published them at the above URL. -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/

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BTRFS snapshot performance - disk vs SSD
by Russell Coker 16 Dec '12

16 Dec '12

btrfs subvol snapshot -r /home /home/backup/$(date +%Y-%m-%d:%H:%M) The above command takes more than 10 seconds on a system with an Intel 120G SSD but less than 1 second on a system with a hard disk identified as "HITACHI HTS72201 DC2Z". Also I've noticed that every system which uses BTRFS on an Intel 120G SSD gives very poor performance when installing Debian packages (which calls sync()). I'm using the ssd and discard mount options. Does the Intel SSD just suck for the type of writes that BTRFS does when synchronising things or is there some way of tweaking it for performance? -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/

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3g NO CARRIER
by James Harper 16 Dec '12

16 Dec '12

I have an OpenWRT box set up on my network that dials up via 3G and then launches an OpenVPN connection to a remote server. The idea of this is so that if something goes wrong with the main router I can connect to the remote server, back through the OpenVPN connection and onto the network. The reason for the OpenVPN connection is that the 3G connection doesn't have a static IP and is also NAT'd by the carrier so isn't externally accessible even if I knew the external IP (eg dyndns wouldn't help me). At some point in the last few weeks it has stopped working though. The last thing I see in the logs when it tries to connect is: Dec 16 15:19:32 bitgw2 local2.info chat[7031]: ATD*99***1#^M^M Dec 16 15:19:32 bitgw2 local2.info chat[7031]: NO CARRIER Dec 16 15:19:32 bitgw2 local2.info chat[7031]: -- failed Dec 16 15:19:32 bitgw2 local2.info chat[7031]: Failed (NO CARRIER) Dec 16 15:19:32 bitgw2 daemon.err pppd[7027]: Connect script failed Dec 16 15:19:33 bitgw2 daemon.info pppd[7027]: Exit. gcom says: Trying list of devices SIM ready Waiting for Registration..(120 sec max) Registered on Home network: "50502",2 Signal Quality: 24,99 Which afaict means that the modem is talking to the base station and that there is some signal available. The next thing I would suspect is the 3G account with the carrier is closed or otherwise broken... is that consistent with a NO CARRIER response or should the modem give some other response? I'm not the account holder so I can't contact the carrier until tomorrow. This was working just fine and nothing has changed so I assume it's an external factor... Is there a command I can send to the modem to find more information? Thanks James

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Likelihood and consequence of MS distributing 'windblows' as a GUI built on Unix/ Linux ?
by Rohan McLeod 14 Dec '12

14 Dec '12

Assembled Illuminati ! Whilst following the thread: "Re: Latest generation laptops with Windows 8 preinstalled, EFI mess.."; the idea occurred that MS might eventually replace or augment Windows; by building it as a GUI plus a Unix / Linux kernel, in the way Apple, now builds the Mac OS as a GUI plus a highly configured FreeBSD kernel (or whatever); is it: 1/ possible 2/ likely and if it happened what would be the consequences ? regards Rohan McLeod

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Re: Latest generation laptops with Windows 8 preinstalled, EFI mess..
by Rick Moen 14 Dec '12

14 Dec '12

Quoting Sam Varghese (sam(a)gnubies.com) > Rick, if you read this guy's article carefully you'll notice that he > makes mention that his installation did not involve secure boot. Ah, good catch. You know, fundamentally, a computer with UEFI Secure Boot enabled _if_ it provides no means in the BIOS to disable that function is just basically not a general-purpose computer, but rather a locked-down single-purpose appliance. If you buy such a thing, you are assuming the risk that your intended repurposing of the machine may be impaired or prevented by the technical measures to prevent unauthorised code running in kernelspace. My own preferred way of dealing with that would be to either (1) replace the BIOS with coreboot, or (2) sell off the offending hardware and get something more suitable. However: Matthew Garrett's shim bootloader and similar solutions provide ways to make UEFI Secure Boot an asset rather than a liability for Linux/BSD/etc. systems, so that's another way around the problem. Anyway, I _still_ continue to think that dual-booting is generally a solution to the wrong problem, and that running alternative OSes (such as MS-Windows ;-> ) in a virtual machine session gives vastly superior operational results. That is, in my experience, users who think they will get good usage out of a dual-boot setup are overly optimistic, and have not stopped to consider how disruptive of one's computing it is to shut everything down and reboot. In the long term, I've noticed, they stay 99.9% of the time in one OS and ignore the other. Which means they've wasted their time and effort. By contrast, a VM approach (given adequate RAM and CPU to make both OSes comfortable) allows and encourages concurrent use of both operating systems.

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