November 2013 - luv-main

Thinking of Oracle Linux
by Russell Coker 11 Nov '13

11 Nov '13

The server which among other things holds my email runs Debian/Wheezy for the Dom0 and most DomUs. It's running Xen for virtualisation and ZFS for data storage. Currently I have some problems, the hardware is defective and has started spontaneously rebooting. This is really bad but a combination of ECC RAM and ZFS means that the risk of data loss is low, but uptime isn't good. The server needs to be replaced so now is a good time to consider other changes. ZFS is not well supported on Linux due to license issues. There are two aspects of this which are particularly important to me, one is that I've found ZFS to cause the kernel to OOM in situations where I think it shouldn't (EG a server with 4G of RAM doing a light Samba load). The other is that ZFS doesn't always start properly on boot so I need to hack the init scripts to make sure it's mounted before starting daemons that depend on it (which doesn't always work, see my message about MySQL). I believe that my coding skills are up to the task of making ZFS work as I desire. But no-one is going to pay me to do that and I don't feel inclined to waste hobby time on work that won't benefit the FOSS community. For reliable data storage on Linux the options are ZFS and BTRFS. The down- side of BTRFS is that it is new and most distributions don't support it as well as one wants for production code. But Oracle apparently support it well. Oracle are also really into Xen and should be able to give better MySQL support than anyone else. The options I'm considering at the moment are using Oracle Linux for the Dom0 and using Debian for the Dom0 with an Oracle kernel. Both of those should be good for running BTRFS and Xen. Debian with an Oracle kernel will make kernel upgrades a little painful but it means I don't have to change the rest of the OS configuration (I've run Debian systems with CentOS kernels before). A complete Oracle OS will work well together but it means I have to change everything to a different OS, admittedly that won't be so hard as the Dom0 does little other than managing DomUs and running MySQL. Any suggestions? -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/

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Linux on Dell servers
by Russell Coker 10 Nov '13

10 Nov '13

I was just looking at the options available on a Dell PowerEdge T110 which has a base price of $749 (it's a nice system, I just bought one for my home). A recent addition to the customisation page (which as far as I recall wasn't there last week when ordering my system) is a huge range of Red Hat and SUSE options. It's nice that Linux options are available, but it's a pity that they don't offer the cheap ones. The T110 makes a nice little workstation/server so one of the desktop licenses for RHEL might be a more useful option. It's rather surprising to see RHEL options going up to well over 20* the base hardware price and SUSE options going up to over 10* the base hardware price. Red Hat Enterprise Linux v6.4, x86_64, 1-2 Sockets, 1 Guest, 1 yr Red Hat Network, FI [add $1,393.70 or $23/week-1] Red Hat Enterprise Linux v6.4, x86_64, 1-2 Sockets, 1 Guest, 3 yr Red Hat Network, FI [add $3,971.00 or $50/week-1] Red Hat Enterprise Linux v6.4, x86_64, 1-2 Sockets, 1 Guest, 5 yr Red Hat Network, FI [add $6,618.70 or $77/week-1] Red Hat Enterprise Linux v6.4, x86_64, 1-2 Sockets, 4 Guest, 1 yr Red Hat Network, FI [add $2,091.10 or $30/week-1] Red Hat Enterprise Linux v6.4, x86_64, 1-2 Sockets, 4 Guest, 3 yr Red Hat Network, FI [add $5,958.70 or $70/week-1] Red Hat Enterprise Linux v6.4, x86_64, 1-2 Sockets, 4 Guest, 5 yr Red Hat Network, FI [add $9,930.80 or $111/week-1] Red Hat Enterprise Linux v6.4, x86_64, 1-2 Sockets, Unlimited Guest, 1 yr Red Hat Network, FI [add $3,485.90 or $45/week-1] Red Hat Enterprise Linux v6.4, x86_64, 1-2 Sockets, Unlimited Guest, 5 yr Red Hat Network, FI [add $16,556.10 or $179/week-1] SuSe Linux Enterprise 11 SP2,1-2SKT,1yr Support With Media(DIB),Physical [add $1,708.30 or $26/week-1] SuSe Linux Enterprise 11 SP2,1-2SKT,3yr Support With Media(DIB),Physical [add $4,495.70 or $55/week-1] SuSe Linux Enterprise 11 SP2,1-2SKT,5yr Support With Media(DIB),Physical [add $6,725.40 or $78/week-1] SuSe Linux Enterprise 11 SP2,1-2SKT,1yr Support With Media(DIB),Unlimited Virtual Licenses [add $2,153.80 or $31/week-1] SuSe Linux Enterprise 11 SP2,1-2SKT,3yr Support With Media(DIB),Unlimited Virtual Licenses [add $5,833.30 or $69/week-1] SuSe Linux Enterprise 11 SP2,1-2SKT,5yr Support With Media(DIB),Unlimited Virtual Licenses [add $8,620.70 or $98/week-1] SuSe Linux Enterprise Server 11 SP2,1-2SKT,1yr Support With Media(FI),Physical [add $1,708.30 or $26/week-1] SuSe Linux Enterprise Server 11 SP2,1-2SKT,3yr Support With Media(FI),Physical [add $4,495.70 or $55/week-1] SuSe Linux Enterprise Server 11 SP2,1-2SKT,5yr Support With Media(FI),Physical [add $6,725.40 or $78/week-1] SuSe Linux Enterprise Server 11 SP2,1-2SKT,1yr Support With Media(FI),Unlimited Virtual Licenses [add $2,153.80 or $31/week-1] SuSe Linux Enterprise Server 11 SP2,1-2SKT,3yr Support With Media(FI),Unlimited Virtual Licenses [add $5,833.30 or $69/week-1] SuSe Linux Enterprise Server 11 SP2,1-2SKT,5yr Support With Media(FI),Unlimited Virtual Licenses [add $8,620.70 or $98/week-1] Red Hat Virtualization (DIB) add $0.00 -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/

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Face-to-face meet-up before Tuesday's event?
by Carl Turney 10 Nov '13

10 Nov '13

Hi All, Would any of you be willing to briefly meet me face-to-face in the Melbourne CBD, before tomorrow's (Tuesday's) LUV meeting? I'd love to attend the meet, but have a more pressing engagement at the same time. But I've also got a frustrating problem with my laptop's plug-in mic. (Works in some contexts, not in others. Have spent much time reading various sources, all without resolution.) Am certain that someone with strong Linux skills would quickly notice what the issue is. If so, please contact me directly by text or email, to arrange a time and location. Thanks VERY much. Carl Turney Far out in the Eastern suburbs Mobile 0427 024 735

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Hibernate and Suspend
by Andrew Greig 10 Nov '13

10 Nov '13

Hi all. Things with Suse 12.2 were fine as far as suspend and shutdown were concerned on both my desktop and notebook computers. The arrival of 12.3 heralded a less than satisfactory behaviour. I have put up with this for some time, but enough! is enough! I have done some reading and discover that suspend writes everything to Ram and then keeps the ram powered up to retain it all, a meagre power demand. Hibernate writes everything open to the swap partition and then on reboot should resume very quickly. Hibernate works for me for 5 minutes but not 8 hours, suspend is also flaky in that the recovery tends to hang with no display. Shutdown hangs on exit unless the previous command was suspend in which case it works as expected. Is this a case of ACPI not being consistent with the BIOS? Should I add "no_acpi" to the grub file? A new release of Suse is only 18 days away, should I see what the upgrade brings? I would be grateful for advice in this, Many thanks Andrew Greig

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Re: redirecting error on internet access
by zlinw＠mcmedia.com.au 09 Nov '13

09 Nov '13

For the sake of "completeness", I put up the following....... As an experiment I issued the command "pdnsd-ctl empty-cache", this clears pdnsd's cache and resets any local rules. interestingly this cured the problem. It also sped up the internet access a good bit. I believe given what has happened that this would be worth while to do say on a yearly basis. When I first installed pdnsd, I remember the time reduction accessing almost all web pages was very much reduced. I felt over time that this reduction appeared to largly dissapear. I asssumed it did not have as much effect on the 3g broadband, this assumption does not appear to be correct. It seems the longer pdnsd runs the more bogged down it gets, or possibly the more rubbish entries ends up in the cache. It's nice to know my initial diagnosis of a name server problem was correct. Lindsay

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mysqld_safe seems unsafe
by Russell Coker 08 Nov '13

08 Nov '13

It's always a sign of low code quality when a daemon has a wrapper script to restart it when it crashes. Squid used to have such a script but for many years has been considered to be reliable enough not to need it. MySQL seems to be the only commonly used daemon with such a script. I had been wondering if the script was even needed, I would have hoped that mysqld was reliable many years ago. But I checked the logs of a RHEL4 system I run and found 19 log messages about mysqld getting signal 11 since 2006 of which the last one was 4 days ago. One problem with such scripts seems to be the issue of reliably shutting down the server. I have a ZFS system that doesn't always mount the filesystems on boot so I use /etc/rc.local to restart mysqld. That usually works apart from the time when I ended up with two copies of mysqld running at once. However mysqld uses file locking and it seems that you don't get data loss when you have two copies of it running at the same time (try not to test this theory on production networks). While it was handy that mysqld was restarted 19 times, it wasn't good that I was unaware of the problems. Is that script being used in the MySQL successors such as Drizzle? -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/

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LUV's Month of Games
by Lev Lafayette 08 Nov '13

08 Nov '13

On Thu, November 7, 2013 6:44 pm, Lev Lafayette wrote: > > On Thu, November 7, 2013 3:20 pm, Steve Roylance wrote: >> there are some browser games at this site, at least one works in firefox >> on fedora 19. Free to play with some micro-transactions, which are >> mostly avoidable. >> >> http://en.gameforge.com/browser-games > > Great collection Steve, thanks for that. The first post for LUV's "month > of games"! > > I promise to get my talk on the website by tomorrow morning... As promised, MMORPGs and Linux available here: http://levlafayette.com/files/2013-luv-mmorpg.pdf ... and here: https://luv.asn.au/files/2013-luv-mmorpg.pdf Also changed to luv-main, because it is relevant to Linux :) All the best, -- Lev Lafayette, BA (Hons), GCertPM, MBA mobile: 0432 255 208 RFC 1855 Netiquette Guidelines http://www.ietf.org/rfc/rfc1855.txt

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redirecting error on internet access
by Lindsay Sprinter 07 Nov '13

07 Nov '13

I am getting an error on one of my internet access points, if you try and access a web page using say iceweasel one gets a delay of around 3 or 4 seconds then an error message is displayed saying something like "Iceweasel has detected the request being redireted to many times and its not likely to succeed, problem could be cured by enabling or disabling cookies or it could be a server error". Anything else such as an ftp transfer simple gets no response. Now I have a small network here one of the machines acting as the internet access point and firewall. The fire wall is just a small script enacting a "don't speak until spoken to" firewall, the script only acting on a single interface ppp0. There are two access points the first is a 3g mobile broadband modem using Virgin, the second a telephone line dial up modem. This is kept as a backup as the the 3g __CANNOT__ be relied on. Both of these are accessed via the "pon" command, only one is ever used at a time, hence only ppp0 is used. The problem __ONLY__ occurs on the 3g broadband access, the land line being quite OK. Anyone have any ideas on this, it would seem to me that virgin network is doing something strange. Lindsay

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AMD64 graphics driver crash.......
by Lindsay Sprinter 06 Nov '13

06 Nov '13

Hi I am looking for a bit of recent motherboard experience here. I have figured out the cause of the crash's of the Nvidia closed src drivers during my recent i386 V AMD64 experimnents. The problem almpst certainly being a buggy motherboard. The board concerend is a Gigabyte GA-X79-UD5. Its always given a little bit of trouble including problems with the hardrives and one particular graphics card (Radeon HD7870) will not work in text mode, graphics mode though being OK. In both cases the equipment concerned has worked OK on other MB's. Search's on the net also said the some of the early X79 chipsets had some problems. Now I have decided after some thought to replace the MB and have narrowed the search down to 2 examples the first is a Gigabyte GA-X79-UP4, this being an almost perfect direct dropin replacement. The second is an ASUS P9X79 Pro. The reasons for considering the ASUS are firstly I am slightly gun shy of Gigabyte boards due to current problem, second I have two other systems that use ASUS P6X58 pro MB's, these being the previous generation of the X79 boards and these boards have given no trouble and been excellent performers. Third the ASUS boad is slightly more "future proof". Now the question is only minor, the ASUS webs site says the board is only rated for windows 7 and latter although the site does provide drivers for Windows XP. The System has (of course) Linux installed, currently this is Debian Sid i386, with the NVidia closed src driver installed and working OK. Windows XP is also installed, Now the question (finally???) is is there likely to be any problem's installing XP on this newer board. Its not a real great tragedy if one cannot install it but it would be nice to have. I would normaly search the net for the answers for this kind of problem but the dial up line though make this far to slow these days as the net currently expects everyone to have highspeed broadband (my high speed access currently being out of service). Using Linux for now over 20 years, Lindsay

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deactivate vg with offline pv's
by James Harper 06 Nov '13

06 Nov '13

I have a server that has an iscsi connection that should have been disabled, and the volume group is enabled on it. I noticed the volume group after I had disconnected the iscsi connection, and am trying not to add the iscsi back, or to reboot the server. lvscan gave a billion errors but I used dmsetup to manually remove the entries for the lv's. Now I just have the volume group that something seems to know about as when I do vgchange I get: # vgchange -a n vg-drbd /dev/mapper/mpathd: read failed after 0 of 4096 at 3900547923968: Input/output error /dev/mapper/mpathd: read failed after 0 of 4096 at 3900547981312: Input/output error /dev/mapper/mpathd: read failed after 0 of 4096 at 0: Input/output error /dev/mapper/mpathd: read failed after 0 of 4096 at 4096: Input/output error Volume group "vg-drbd" not found I want to tell the kernel to forget that vg-drbd exists altogether as it is no longer reachable and shouldn't be on that machine anyway. Any suggestions? Thanks James

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