luv-main September 2011

luv-main@luv.asn.au

53 participants
57 discussions

by Jason White

I just realized (too late, unfortunately) that Mutt's reply to list feature is now generating a "To" field like this: luv-main(a)lists.luv.asn.au, luv-main(a)luv.asn.au I think the cause may be this header in messages distributed via the list: List-Post: <mailto:luv-main@lists.luv.asn.au> whereas the "To" header gives luv-main(a)luv.asn.au as the address. Would it be possible for our hard-working and diligent administrators to get rid of the lists.luv.asn.au domain in the headers? I don't know enough about mailman configuration to appreciate how much work this would require. I might be able to work around this in my Mutt configuration, but I think it's best fixed at the source, if possible.

11 years, 6 months

Re: [luv-main] Bought a laptop with optimus, doesn't work (nice false advertising nvidia). Now wanting to murder nvidia via Open Letter.

by Jeremy Lunn

On 12/09/2011, at 6:50 PM, Trent W. Buck wrote: >> this has to be illegal. > > Under what law? Depending on the claims being made (and perhaps where/how), it could be a form of misleading or deceptive conduct under the Competition and Consumer Act 2010 (formerly Trade Practices Act 1974). There is a bit of info here on misleading and deceptive conduct under Australian consumer law at: http://www.accc.gov.au/content/index.phtml/itemId/815335 Jeremy

11 years, 6 months

[luv-main] Default grub options for RHEL6 ?

by Chris Samuel

Hi folks, Anyone know what the default grub options you get on a RHEL6 box are ? Do they include acpi=off ? If so, is that conditional upon something that Anaconda/kickstart detects ? Or something that must be explicitly selected ? (Got a friend in the US who has found a box with acpi=off set, which is bad for NUMA hardware if the kernel is relying on ACPI to get that info). cheers, Chris -- Chris Samuel : http://www.csamuel.org/ : Melbourne, VIC This email may come with a PGP signature as a file. Do not panic. For more info see: http://en.wikipedia.org/wiki/OpenPGP

11 years, 6 months

[luv-main] PostgreSQL benchmarked on XFS vs ZFS vs btrfs vs ext4

by Toby Corkindale

Resending this now the LUV list seems to be back up, as I never saw it come through yesterday. Apologies if this is a duplicate. -------- Original Message -------- Hi, Some months ago, I ran some (probably naive) benchmarks looking at how pgbench performed on an identical system with differing filesystems and mount options. Since then some of you have pointed out that ZFS is looking pretty good on Linux now, and I'm sure there's been a bunch of btrfs fixes too, and no doubt various updates in the Linux kernel and PostgreSQL that should help performance. I ran the tests on Ubuntu 11.04 with Pg 9.0 first, then upgraded the system to Ubuntu 11.10 (beta) with Pg 9.1 and ran them again. The latter combination showed a considerable performance improvement overall - although I didn't investigate to find out whether this was due to kernel improvements, postgres improvements, or virtio improvements. The results are measured in transactions-per-second, with higher numbers being better. Results: ext4 (data=writeback,relatime): natty: 248 oneiric: 297 ext4 (data=writeback,relatime,nobarrier): natty: didn't test oneiric: 1409 XFS (relatime): natty: didn't test oneiric: 171 btrfs (relatime): natty: 61.5 oneiric: 91 btrfs (relatime,nodatacow): natty: didn't test oneiric: 128 ZFS (defaults): natty: 171 oneiric: 996 Conclusion: Last time I ran these tests, xfs and ext4 pulled very similar results, and both were miles ahead of btrfs. This time around, ext4 has managed to get a significantly faster result than xfs. However we have a new contender - ZFS performed *extremely* well on the latest Ubuntu setup - achieving triple the performance of regular ext4! I'm not sure how it achieved this, and whether we're losing some kind of data protection (eg. like the "barrier" options in XFS and ext4). If ext4 has barriers disabled, it surpasses even ZFSs high score. Perhaps some of you can shed some light on this for me? Oddly, ZFS performed wildly differently on ubuntu 11.04 vs 11.10b. I can't explain this, as the ZFS kernel module was identical (coming from a third-party apt repository). Any ideas? Cheers, Toby

11 years, 6 months

[luv-main] IPSec over IPv6 - packet routing

by Jason White

I've raised this on the StrongSwan list over the last several weeks, but with no reply so far - hence I'm raising the question here as well to gain a broader audience. I have been experimenting with Strongswan as an implmentation of IKEv2 (my ultimate interest is also in its implementation of mobile IPv6, but that's not of immediate concern). If I set up an IPSec tunnel with StrongSwan 4.5.2 between my laptop and an external host (or a virtual machine and another host with a single network interface such as eth0) all appears to work; but my desktop machine has both eth0 and ppp0 interfaces. The tunnel appears to be established correctly on both sides and the IPSec policy appears to be correct, but my machine can't send packets over the tunnel. The kernel log contains messages regarding pmtu discovery, and packet monitoring shows that neighbour discovery packets are being sent out the eth0 interface rather than ppp0, i.e., if I try to ping the remote host over the tunnel, I get a lot of neighbour discovery packets on eth0, whereas the traffic needs to be routed through the ESP encapsulation to ppp0 and onward to the destination. Obviously I can provide much more detail; the main problem at this stage is how to bring the problem to the attention of someone who is familiar with Linux IPSec sufficiently to identify the cause. I may yet get a response on the strongSwan list, of course.

11 years, 6 months

[luv-main] source the output of a file

by James Harper

I have a command that has output like: VAR1=A VAR2=B VAR3=C I want to execute that command in a shell script such that those statements are execute into my environment, so $VAR1 is now equal to 'A'. I can just put the output in a temporary file and then source that file, but is there a more direct way? Thanks James

11 years, 6 months

[luv-main] iet or tgt?

by James Harper

Has anyone used iet or tgt and can comment on the performance? I am using iet at the moment because it's what I've used before and because tgt doesn't have 'iscsi' in the package name I missed it when I was first searching the Debian archives, but tgt seems to have a few features that might be nice. Thanks James

11 years, 6 months

Re: [luv-main] Thank-You (Was: LUV lists; down-time and unsubscribe notice)

by Tony Langdon

At 07:29 PM 9/15/2011, Joel W Shea wrote: >On 15 September 2011 17:40, Peter Lieverdink ><me(a)cafuego.net> wrote: <...> > Earlier this >week LUVs mail server broke down and a current >backup of the list subscribers was not >available. As I setup new lists ysterday, I >temporarily used an older backup of list >subscribers to populate these new lists. > > >Today I rescued current subscriber data from the >old server and used that to populate the new >lists. Before I did that, I had to clear the >lists, and I forgot to make the system NOT send >notifications when doing that. You were all >(silently) re-subscribed approximately a minute >later. > I know this kind of work can usually go >underappreciated, so here's a big >THANKYOU!OU! > Apologies if I caused any >unnecessary freak-outs :-) If it weren't for >that, or the slight change in the domain in the headers; I think we'd barely Thank you for such a smooth changeover. If it wasn't for the change of domain and that little slip with the unsubscribe, I'd have not really noticed. Good job and much appreciated. :) 73 de VK3JED / VK3IRL http://vkradio.com

11 years, 6 months

[luv-main] Thank-You (Was: LUV lists; down-time and unsubscribe notice)

by Joel W Shea

On 15 September 2011 17:40, Peter Lieverdink <me(a)cafuego.net> wrote: <...> > Earlier this week LUVs mail server broke down and a current backup of the list subscribers was not available. As I setup new lists ysterday, I temporarily used an older backup of list subscribers to populate these new lists. > > Today I rescued current subscriber data from the old server and used that to populate the new lists. Before I did that, I had to clear the lists, and I forgot to make the system NOT send notifications when doing that. You were all (silently) re-subscribed approximately a minute later. > I know this kind of work can usually go under–appreciated, so here's a big THANK–YOU! > Apologies if I caused any unnecessary freak-outs :-) If it weren't for that, or the slight change in the domain in the headers; I think we'd barely even notice there was an issue > The list archives are not yet available on the new system, but rest assured these archives were backed up properly and are not lost. You'll be notified when the come back online. Once again, thanks for the recovery effort. (Apologies to everyone for the slight cross-post) -- Joel Shea <jwshea(a)gmail.com>

11 years, 6 months

[luv-main] Routing change handling in recent kernels.

by Deon George

I'm hoping somebody can help me understand what has changed in recent kernels, with regard to routing. I'm having a problem with Centos 6 hosts (and the same problem I had with a Ubuntu 10.10 host), that I dont have with Centos5 hosts. I can only conclude that its changes in IP handling that may have occurred with these later kernels. (Or changes in IP kernel configuration in these later distros?) I have this configuration: * Firewall Router eth0 10.10.3.1/26 PPOEServer (running over eth0) - handing out public addresses to pppoe clients * Centos 5 hosts (many) eth0 10.10.3.0/26 - (with a route 10/8 via this interface) ppp0 (running over eth0) - getting a A.B.C.x address (this is a public accessible address) * My laptop eth0/wlan0 10.10.3.128/26 (a different interface on the router) My laptop has been very successful in communicating with C5 hosts via eth0 address and ppp0 address. Specifically, on my laptop, when I connect to A.B.C.x, the packet arrives on the host on the ppp0 interface, and the reply goes out the eth0 interface (because of a default 10/8 route via that interface). Obviously if I talk to the host on its 10.10.3.0/26 address, the packet arrives and leaves via the eth0 interface. I implemented both Ubuntu 10.10 and Centos 6 servers with exactly the same configuration, ie: eth0 10.10.3.0/26 ppp0 (running over eth0) - getting A.B.C.x address However, I cannot talk to the hosts via the ppp0 interface, when I'm on a network that the reply would go via the eth0 interface. Specifically, if the packet arrives on the ppp0 interface and *would* leave via the eth0 interface, it appears as if the host is not even processing the packet. iptables confirms that it doesnt count the packets coming in. Chain INPUT (policy ACCEPT 0 packets, 0 bytes) pkts bytes target prot opt in out source destination 0 0 all -- ppp0 * 0.0.0.0/0 0.0.0.0/0 If I communicate with the host, where the packet arrives and leaves on the same interface - no problem. If I change my routing so that access to my laptop (10.10.10.128/26) is back via the ppp0 interface - then all is good (but not want I want) - if I access the host via its 10.10.3.0/26 address, then no problems either - again not really what I want. Here's some network tracing to show whats going on... (And yes, all this is done with firewall rules turned off - to make sure that there wasnt an offending rule) Here is what I see (if I ping the host via its A.B.C.x address from my laptop 10.10.3.130) Router (pppoes interface): 10:41:45.461588 IP 10.10.3.130 > A.B.C.28: ICMP echo request, id 38224, seq 1, length 64 10:41:46.461205 IP 10.10.3.130 > A.B.C.28: ICMP echo request, id 38224, seq 2, length 64 10:41:47.460768 IP 10.10.3.130 > A.B.C.28: ICMP echo request, id 38224, seq 3, length 64 10:41:48.461881 IP 10.10.3.130 > A.B.C.28: ICMP echo request, id 38224, seq 4, length 64 Host: (ppp0) (ICMP echo, but no reply) listening on ppp0, link-type LINUX_SLL (Linux cooked), capture size 65535 bytes 10:41:44.220727 IP 10.10.3.130 > A.B.C.28: ICMP echo request, id 38224, seq 1, length 64 10:41:45.219741 IP 10.10.3.130 > A.B.C.28: ICMP echo request, id 38224, seq 2, length 64 10:41:46.218733 IP 10.10.3.130 > A.B.C.28: ICMP echo request, id 38224, seq 3, length 64 10:41:47.219735 IP 10.10.3.130 > A.B.C.28: ICMP echo request, id 38224, seq 4, length 64 Host: (eth0) (only the PPPoE packets - no reply) listening on eth0, link-type EN10MB (Ethernet), capture size 65535 bytes 10:41:44.219726 PPPoE [ses 0x4b] IP 10.10.3.130 > A.B.C.28: ICMP echo request, id 38224, seq 1, length 64 10:41:45.219005 PPPoE [ses 0x4b] IP 10.10.3.130 > A.B.C.28: ICMP echo request, id 38224, seq 2, length 64 10:41:46.218227 PPPoE [ses 0x4b] IP 10.10.3.130 > A.B.C.28: ICMP echo request, id 38224, seq 3, length 64 10:41:47.218992 PPPoE [ses 0x4b] IP 10.10.3.130 > A.B.C.28: ICMP echo request, id 38224, seq 4, length 64 And for info, here's hosts routing table: 172.31.3.1 0.0.0.0 255.255.255.255 UH 0 0 0 ppp0 10.10.3.0 0.0.0.0 255.255.255.224 U 0 0 0 eth0 169.254.0.0 0.0.0.0 255.255.0.0 U 1002 0 0 eth0 10.0.0.0 10.10.3.1 255.0.0.0 UG 0 0 0 eth0 0.0.0.0 172.31.3.1 0.0.0.0 UG 0 0 0 ppp0 What's changed in the new kernels - or the new distro versions? ...deon

11 years, 6 months

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luv-main September 2011