Re: How to make systemd more reliable

[Chris Samuel via luv-main]

On Thursday, 29 September 2016 5:00:39 PM AEST Andrew Pam wrote:

> I miss TECO.  Oh no, wait, no I don't.

Grin, I think I missed that one, instead having to use FRED on a Honeywell L66 
running GCOS-3 (from memory).  That was a pure line editor, because the L66 
only had a line input mode as there was a front end system between you and the 
main machine that only passed on input/output when hit hit enter. :-)

https://www.thinkage.ca/english/gcos/expl/fred/expl.html

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Re: another outage

[Chris Samuel via luv-main]

On Friday, 23 September 2016 6:48:35 PM AEST Russell Coker via luv-main wrote:

> The LUV server is not running BOINC.
> 
> The LUV server is a VM hosted on a system that runs BOINC among other
> things.

Ahh, thanks for the explanation. Odd that services on one VM can kill another.

cheers,
Chris
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Re: Orbital simulation

[Chris Samuel via luv-main]

On Friday, 23 September 2016 1:59:16 PM AEST Russell Coker via luv-main wrote:

> Is there a good free orbital simulator for Linux?
> 
> I don't want a game like KSP but a simulation of orbits without much need
> for fancy graphics.

How about this?

http://gmatcentral.org/

# Do you want to go to Mars but don't know when to leave or how much to bring?
#   Do you want to land something on the moon?  The General Mission Analysis
# Tool (GMAT) is an open-source space mission analysis tool to answer just
# those  types of questions.  GMAT is developed by a team of NASA, private
# industry,  public, and private contributors. GMAT is intended both for
# real-world engineering design studies and as a tool for education and public
# engagement in the spirit of the NASA Charter.

All the best,
Chris
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Re: another outage

[Chris Samuel via luv-main]

On Friday, 23 September 2016 4:48:47 PM AEST Russell Coker via luv-main wrote:

> I've configured BOINC to only use 40% of RAM and increased swap size.

I've got to ask - what's the rationale for running BOINC on the LUV server?

Thanks for the outage report.

All the best,
Chris
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Re: Postfix + Dovecot (+MySQL)

[Chris Samuel via luv-main]

On Wednesday, 21 September 2016 9:40:53 PM AEST Erik Christiansen via luv-main 
wrote:

> On debian, there is also:
> 
> $ apt-cache search vacation

Fedora/RHEL use the port of the 386bsd vacation program, the maintainer of 
which you may be familiar with (not that I've had to do much maintenance 
recently!).

http://www.csamuel.org/software/vacation

The Debian one is nice too, I actually use that on my home VM as it's Debian 
based. :-)

cheers,
Chris
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Re: Postfix + Dovecot (+MySQL)

[Chris Samuel via luv-main]

On Tuesday, 20 September 2016 9:00:08 AM AEST Piers Rowan via luv-main wrote:

> The only thing left to do is set up vacation emails - any suggestions?
> Preferably with a way for users to manage them themselves (bearing in mind
> the Dovecot / SASL / MySQL thingo)

Never tried it, but I just found this with a quick search:

http://vacation-web.sourceforge.net/

Best of luck!
Chris
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Re: Can anyone make suggestions for training / learning resources wrt databases.

[Chris Samuel via luv-main]

On Sunday, 18 September 2016 10:54:06 AM AEST h via luv-main wrote:

> I am NOT looking for specific answers to these problems, but rather
> some teaching / groundwork information about relational databases /
> sql / postgis concepts.

I've seen this recommended as an introduction to PostGIS:

http://workshops.boundlessgeo.com/postgis-intro/

There is also this book:

https://www.manning.com/books/postgis-in-action-second-edition

and this Irish university has powerpoint slides of a GIS course online:

http://www.comp.dit.ie/pbrowne/Spatial%20Databases%20SDEV4005/Spatial%20Databases%20SDEV4005.htm

All the best,
Chris
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Re: OT: trains & demand tariffs [Was: outage]

[Chris Samuel via luv-main]

On Saturday, 17 September 2016 1:23:34 AM AEST Anthony via luv-main wrote:

> This is primarily for "in home displays", but presumably there's gotta be a
> device that's linux friendly out there that talks Zigbee Power v1?

This is what Richard Keech recommended to me:

https://rainforestautomation.com/rfa-z106-raven/

which I bought from these folks:

http://www.fastnetworks.com.au/new-products/9dm7ondccxpc6michdc7182zm0cq7b

and it does work under Linux - at least in so far that it presents a character 
device like a modem to the OS.

The problem is that I live in AusNetServices land where their flash based 
website (sigh) has been saying since 2014 that:

# ZigBee management is currently under pilot and is not currently available.
# Enter access code to continue.

I've prodded them a few times about this and the last time (back in April) 
they told me it might be available in August, but nothing yet. :-(

All the best,
Chris
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Re: Change HDMI resolution via fbset?

[Chris Samuel via luv-main]

On Tuesday, 13 September 2016 2:40:28 AM AEST Toby Corkindale via luv-main 
wrote:

> Am I doing it wrong? Or is it possible that the framebuffer device for this
> video device just doesn't let you change the resolution?

Does this help?

https://wiki.archlinux.org/index.php/GRUB/Tips_and_tricks#Setting_the_framebuffer_resolution

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Re: Hardware for kids

[Chris Samuel via luv-main]

On Tuesday, 30 August 2016 11:03:31 AM AEST Tim Connors via luv-main wrote:

> I yearn for the days when computers didn't suck.

They always have, they've just found different ways to express it these days.

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Re: Hardware for kids

[Chris Samuel via luv-main]

On Monday, 29 August 2016 12:27:08 PM AEST Paul van den Bergen wrote:

> IIUC, someone recently released the golden key that is part of the security
> system underpinning UEFI anyway... the inherent danger of golden keys
> etc...

It wasn't a key that leaked.

http://mjg59.dreamwidth.org/44223.html

All the best,
Chris
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Re: M.2 and SSD

[Chris Samuel via luv-main]

On Monday, 15 August 2016 9:38:00 PM AEST Andrew McGlashan via luv-main wrote:

> And I just learnt that the flash used in most SSDs is pretty much
> equivalent these days; however, Samsung has the best firmware/management
> of the flash -- so it is the one to go for.

Sam McLeod (who did the awesome talk about building high performance storage
for LUV last year) said to me (via Twitter):

# don't touch anything Samsung in our experience. Go Micron M600
# or Sandisk Extreme Pro

He was pretty down on their firmware.   However, Peter Tonoli from unimelb said
he'd not had any issues with Samsung 850pro's, but he takes care to never run
them over 50% occupancy.

Samsung did manage to ship a firmware update 18 months ago that b0rked a some
peoples drives.

http://www.guru3d.com/news-story/after-samsung-840-evo-issues-now-the-850-pro-has-issues-too.html

cheers,
Chris
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Re: Linux TCP security flaw?

[Chris Samuel via luv-main]

On Saturday, 13 August 2016 11:50:27 AM AEST Chris Samuel via luv-main wrote:

[quoting LWN]
> # The fix has not made it to the stable kernels yet,

There is also this comment on the article:

https://lwn.net/Articles/697130/

# The patches addressing CVE-2016-5696 are available in the public
# stable queue tree, and are very likely to be present in the next
# round of stable releases.

So hopefully soon..

cheers,
Chris
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Re: Linux TCP security flaw?

[Chris Samuel via luv-main]

On Friday, 12 August 2016 5:21:43 PM AEST Erik Christiansen wrote:

> Is the article perhaps a furphy?

The attack is quite real, LWN has a nice little summary here:

https://lwn.net/Articles/696868/

It's subscriber content only until Thursday (from memory) but LWN is an 
awesome website and they are really need (and deserve) the communities 
support.

One thing it says there is:

# Cao did alert kernel developers to the problem, which was fixed in
# the mainline in July (and appears in the 4.7 kernel). The fix raises the
# limit to 1000 challenge ACKs per second, but also adds some
# randomization to the value so that counting will be less effective. In
# addition, the patch notes per-socket rate-limiting is available, which
# could lead to the removal of the global challenge ACK count down the
# road; some work toward that end has been merged as well.
#
# The fix has not made it to the stable kernels yet, but there is a
# mitigation available in the form of the tcp_challenge_ack_limit
# sysctl knob. Setting that value to something enormous (e.g. 9)
# will make it much harder for attackers to exploit the flaw.

All the best,
Chris
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Gmane web interface down

[Chris Samuel via luv-main]

Hi folks,

In case you're not aware the Gmane admin Lars has shut down the web interface 
for Gmane as he's too overloaded to keep it going:

https://lwn.net/Articles/695695/

Originally it was going to be the NNTP side as well, but he's now  said he's 
going to keep that up for now.

Lars original blog on this is here:

https://lars.ingebrigtsen.no/2016/07/28/the-end-of-gmane/

but the LWN article has constructive comments and an update on the change of 
heart that means the NNTP interface will keep going for now at least.

All the best,
Chris
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MySQL Galera (Percona XtraDB Cluster) aborts on startup after successful SST

[Chris Samuel via luv-main]

Hi folks,

Anybody got any clues about what to do when the sole message you get regarding
a problem when starting up Percona XtraDB Cluster (basically MySQL with Galera
clustering built in) is just this?

Jun  8 11:43:58 hostname mysqld: 160608 11:43:58 [ERROR] Aborting

It's preceded by lots of log messages about a successful SST and followed by 
lots of
log messages about it successfully shutting down but it seems to be missing the 
bit
where it says *WHY* it's aborting.. :-(

The version information is right before that abort message, and says:

Jun  8 11:43:58 hostname mysqld: 160608 11:43:58 Percona XtraDB 
(http://www.percona.com) 5.5.41-37.0 started; log sequence number 876619301144

There's more context over on my post on the Percona forums here:

https://www.percona.com/forums/questions-discussions/percona-xtradb-cluster/44511-freshly-installed-pxc-5-5-41-37-0-box-aborts-with-no-diagnostics-after-successful-sst

Anyone got any ideas at all about how to get more info out?

cheers!
Chris (who's been troubleshooting this for days now)
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Re: strange TCP problem looks like PMTU but isn't

[Chris Samuel via luv-main]

On Thursday, 28 April 2016 10:46:31 AM AEST Russell Coker via luv-main wrote:

>  but "ping -M want -s 1400 8.8.8.8" works without any problems

I usually use "-M do" for that sort of testing.

The "tracepath" program will also show you the MTU along the route (as long as 
UDP isn't being blocked).

...and from bitter experience I would suggest doing the same test in the 
reverse direction; at work we were having problems for a while with sites 
outside using jumbo frames until we learnt that the uni had asymetric routing 
and the return path had a different MTUon one segment to the incoming path.

Oh, and some bright spark had decided that they could save IP's by using 
RFC1918 addresses on those segments and so the router was sending out PMTUD 
ICMP's with addresses that would get dropped at the border. :-/

Good luck!
Chris
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Re: greylisting

[Chris Samuel via luv-main]

On Tuesday, 19 April 2016 3:09:22 PM AEST Trent W. Buck via luv-main wrote:

> I'm using postgrey still because my postfix is f'ing ancient.

I started off using postgrey but switched to sqlgrey as it is (or at least was 
then) pretty clever in learning about systems that retry correctly.

http://sqlgrey.sourceforge.net/

# The main drawback of grey-listing as it was done in early implementations
# was the delaying of legit emails.
#
# This is nearly solved by the auto-white-listing mechanisms built
# into SQLgrey:
# 
# When a sender has been seen coming from a given IP address, it
# is automatically accepted when coming again from the same IP address.
#
# When several senders from the same domain have been seen coming
# from the same IP address, senders from the same domain are accepted
# when coming from the same IP address.
#
# The delay shouldn't really be a drawback anymore: users will only
# experience delays (mostly in the 6 to 30 minutes range) when receiving
# the first email from a given sender. And on a large scale, new senders
# from a given domain are automatically accepted from the IPs previously
# used for this domain email traffic.

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Re: mjg59 | Skylake's power management under Linux is dreadful and you shouldn't buy one until it's fixed

[Chris Samuel via luv-main]

On Friday, 15 April 2016 5:08:15 PM AEST Trent W. Buck via luv-main wrote:

> I think that part matters even for mains-powered Skylake systems.

Apparently not, the article says:

# (Edit to add: this issue is restricted to the mobile SKUs.
# Desktop parts have very different power management behaviour)

Which is good to hear!

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Re: Impending Crypto Monoculture

[Chris Samuel via luv-main]

On Friday, 15 April 2016 9:46:40 AM AEST Chris Samuel via luv-main wrote:

> There is an interesting rebuttal of the fanboyism remark in the LWN article
> in  one of the comments here:

Grr...  hit the shortcut to send once, got a popup dialog saying that this 
shortcut can lead to accidentally sending messages and giving me a range of 
options, the first of which was to disable the shortcut, which I did.

Hit that again and it sent it without prompting!  Sigh...

Here's the link I was about to insert.

https://lwn.net/Articles/682260/

cheers,
Chris
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Impending Crypto Monoculture

[Chris Samuel via luv-main]

Hi folks,

Given the ongoing crypto discussion I thought this post on LWN "The prospect 
of a crypto monoculture" from a few weeks back (publicly available now) might 
be of interest:

https://lwn.net/Articles/681615/

It's a discussion of Peter Gutmann's post to comp.encryption.general entitled 
"On the Impending Crypto Monoculture" about how we are heading towards a 
situation where the only strong encryption that seems well designed is both 
designed and implemented by a single group, led by Dan Bernstein.

There is an interesting rebuttal of the fanboyism remark in the LWN article in 
one of the comments here:


Peter's post is archived here:

https://lwn.net/Articles/681616/

Peter has been doing crypto for a long time and wrote the excellently titled 
"Everything you Never Wanted to Know about PKI but were Forced to Find Out":

https://www.cs.auckland.ac.nz/~pgut001/pubs/pkitutorial.pdf

It's an interesting situation, though I think I'd trust Dan a bit more than I 
trust the USG now. :-)

All the best,
Chris
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Re: SP Ausnet and ZigBee devices

[Chris Samuel via luv-main]

On Saturday, 9 April 2016 10:38:41 PM AEST Chris Samuel via luv-main wrote:

> So I guess we've got some time to wait still...

I prodded them via their Zendesk support site and got this response:

# At this point of time, AusNet Services does not support the customer
# binding of ZigBee devices (eg In Home Display) to their smart meter.
#
# It will be possible to connect real time devices to most smart meters,
# the estimated time of arrival for IHD devices is August 2016.
#
# Updates will be provided on www.ausnetservices.com.au

So perhaps this year...

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Re: SP Ausnet and ZigBee devices

[Chris Samuel via luv-main]

On Saturday, 9 April 2016 9:41:05 PM AEST Allan Duncan via luv-main wrote:

> Richard Keech gave a talk in August 2014 and I thought he had a kludge 
> to access the data.

I'm pretty sure Richard was on a different supply network who offered a 
service so you could provide your ZigBee devices HW address & they'd program 
the smart meter to permit it to bind.

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Re: SP Ausnet and ZigBee devices

[Chris Samuel via luv-main]

On Saturday, 9 April 2016 9:56:03 PM AEST Ashley Baumann via luv-main wrote:

> I have a Raven USB stick from Rainforest Automation plugged into a raspberry
> pi, talking to my smartmeter.

That's what I've bought, though of course I can't use it until Ausnet decide 
to allow customers to bind ZigBee devices to their meters. :-(

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Re: SP Ausnet and ZigBee devices

[Chris Samuel via luv-main]

On Saturday, 9 April 2016 4:39:06 PM AEST Brian May via luv-main wrote:

> Has anybody had any recent experience talking to smart power meters via
> ZigBee, preferably on Linux? e.g. what hardware? what software?

Still not here, because Ausnet Services horrible Flash based 
MyHomeEnergy.com.au website still says for ZigBee Devices:

# ZigBee management is currently under pilot and is not currently available.
# Enter access code to continue.

Basically it looks like it hasn't changed for 2 years. :-(

I pinged them via twitter to see if there was any news.  Also pinged Greenwave 
who seemed to make the "gateway" device they say you can connect (and for 
which the website does prompt for a MAC address).

Going back through my email I can see that in 2014 I did a support request 
with them and was told:

# At this point of time AusNet Services does not support the customer binding
# of ZigBee devices (eg In Home Display) to their smart meter. In the future,
# it will be possible to connect near-real-time devices to most smart meters
# via ZigBee (IHD). When these devices are connected correctly and have
# reliable communication, devices will be able to show “near real time” power
# usage (1 min readings).
#
# There is active project underdevelopment but there is no fixed time frame
# when ZigBee enablement of smart meters in the AusNet Services network
# will occur – it will be most likely sometimes late this year.

I'm guessing that means they might still be working on it.

I'm going to try and reopen that request to see if there is any news.

Might be worth opening your own request with them too!

Best of luck,
Chris
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Re: spam with bad From: field

[Chris Samuel via luv-main]

On Friday, 1 April 2016 10:22:40 PM AEDT Russell Coker via luv-main wrote:

> Is there a good way of stopping such spam with Postfix and SpamAssassin?

You can match on the display-name in "header" tests with SpamAssassin using 
the :name suffix according to the docs:

http://spamassassin.apache.org/full/3.4.x/doc/Mail_SpamAssassin_Conf.html

# Appending a modifier :name to a header field name will cause everything
# except the first display name to be removed from the header field. It is
# mainly applicable to header fields containing a single mail address: 'From',
# 'Sender', along with their 'Resent-From' and 'Resent-Sender' counterparts.
[...]
# For example, appending :name to a header name will result in "Foo Blah"
# (without quotes) in all of the following cases:
#
# example@foo (Foo Blah)
[...]
# "Foo Blah" 

Best of luck!
Chris
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Re: pxe server

[Chris Samuel via luv-main]

On Sat, 6 Feb 2016 12:36:02 AM James Harper via luv-main wrote:

> I’m trying to set up a PXE server under Debian, but can’t see any packages
> that support the DHCP part of the PXE protocol.

Does this blog post help?

http://danielboca.blogspot.cz/2012/02/boot-linux-from-network-using-pxe-and.html

All the best,
Chris
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Re: SSL configuration

[Chris Samuel via luv-main]

On Sun, 31 Jan 2016 12:56:20 PM Morrie Wyatt via luv-main wrote:

> I agree with Jason here. Bringing people toward best practices should be 
> by education and encouragement, not by blunt instrument.

I agree, if a prospective users first attempt to find out about Linux results 
in 
"I wanted to learn about it, but their website doesn't work" then nobody wins.

All the best,
Chris
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Re: Mail Server Really Slow

[Chris Samuel via luv-main]

On Wed, 20 Jan 2016 08:15:00 PM Craig Sanders via luv-main wrote:

> that's weird because the list munges the From: address, so a reply
> should go to the list.

On the other hand Reply-To: is set back to the original poster.

So I guess it depends whether your MUA prefers List-Post: over Reply-To: 
(which this version of Kmail seems to) or vice-versa.

All the best,
Chris
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Re: Mail Server Really Slow

[Chris Samuel via luv-main]

On Tue, 19 Jan 2016 10:12:12 AM Piers Rowan via luv-main wrote:

> The server is a VM on a host server that also provides http / mysql 
> services. The host server runs cron jobs to poll the email server 
> (importing data from mail boxes into the CRM) so - to clutch at straws - 
> I am not sure if the host and guest are competing for the disk IO at the 
> same time with these calls. Contrary to that is that the host server 
> does not experience any slow downs.

Some ideas that I've not seen mentioned before yet:

1) perf top - to see where the system is spending time as a whole (and if you 
need to drill down on a process you can do perf top -p $PID).

2) latencytop - as long as your kernel has CONFIG_LATENCYTOP

3) iotop - if your version is new enough then the -o option will hide idle 
processes, otherwise just press 'o' when you get the main display.

Best of luck!
Chris
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Re: BTRFS

[Chris Samuel via luv-main]

On Tue, 12 Jan 2016 04:16:27 PM Russell Coker via luv-main wrote:

> BTRFS doesn't support duplicate data blocks (in any normal or desirable
> configuration) unlike ZFS which has the copies= configuration.

David Sterba just released btrfs-progs 4.4 which has a new feature:

# * mkfs.btrfs --data dup
#
#   People asked about duplicating data on a single device for a long time.
# There are no technical obstacles preventing that, so it got enabled with
# a warning about potential dangers when the device will not do the
# duplicated copies.
#
#  See mkfs.btrfs section 'DUP PROFILES ON A SINGLE DEVICE'.

The referenced manual page says:

https://git.kernel.org/cgit/linux/kernel/git/kdave/btrfs-progs.git/tree/Documentation/mkfs.btrfs.asciidoc

# DUP PROFILES ON A SINGLE DEVICE
# ---
#
# The mkfs utility will let the user create a filesystem with profiles that 
write
# the logical blocks to 2 physical locations. Whether there are really 2
# physical copies highly depends on the underlying device type.
#
# For example, a SSD drive can remap the blocks internally to a single copy thus
# deduplicating them. This negates the purpose of increased redunancy and just
# wastes space.
# 
# The duplicated data/metadata may still be useful to statistically improve the
# chances on a device that might perform some internal optimizations. The actual
# details are not usually disclosed by vendors. As another example, the widely
# used USB flash or SD cards use a translation layer. The data lifetime may
# be affected by frequent plugging. The memory cells could get damaged, 
hopefully
# not destroying both copies of particular data.
# 
# The traditional rotational hard drives usually fail at the sector level.
# 
# In any case, a device that starts to misbehave and repairs from the DUP copy
# should be replaced! *DUP is not backup*.


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Re: IPv6

[Chris Samuel via luv-main]

On Fri, 15 Jan 2016 08:51:19 PM Joel W. Shea via luv-main wrote:

> Are there any minutes taken/published for committee meetings?

It's a legal requirement of the act that governs associations in Victoria for 
there to be minutes of committee meetings.

Members have a right to request to see such minutes but the committee has the 
right to refuse or excise parts for various listed reasons.

All the best,
Chris
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Re: SSHD

[Chris Samuel via luv-main]

On Tue, 12 Jan 2016 05:17:12 PM Julien Goodwin via luv-main wrote:

> SMR/Archive is something to avoid unless you're going to use the drives 
> like tape given the ~200MB block size for writes.

...and if you do want to use an SMR drive you need to avoid kernels between 
3.18.21 and 4.4.0-rc3, see:

https://bugzilla.kernel.org/show_bug.cgi?id=93581#c106

for the gory details.

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Re: SPF and DKIM checks on mail to the list

[Chris Samuel via luv-main]

On Wed, 23 Dec 2015 12:25:31 AM Russell Coker via luv-main wrote:

> No mail has been rejected due to changes to the From: field.

Great, so that change will be reverted to make it RFC compliant once more?

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Re: SPF and DKIM checks on mail to the list

[Chris Samuel via luv-main]

On Tue, 22 Dec 2015 03:50:54 PM Russell Coker via luv-main wrote:

> Don't claim that there's something wrong with the LUV server though. 

I'm not, RFC-2822 "Internet Message Format" is (IMHO):

# [...]   The "From:" field specifies the author(s) of the message,
# that is, the mailbox(es) of the person(s) or system(s) responsible
# for the writing of the message.  The "Sender:" field specifies the
# mailbox of the agent responsible for the actual transmission of the
# message. 

It appears to me that what should go in the Sender: field is instead ending up 
in the From: field and that seems to be in clear breach of the RFC.

All the best,
Chris
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Re: Getting systemd to not use cpuacct cgroup on RHEL 7.2

[Chris Samuel via luv-main]

On Tue, 22 Dec 2015 06:59:24 PM Clinton Roy via luv-main wrote:

> Might do what you need?

An interesting idea.

> This doesn't stop systmed from mounting the cgroups, it just tells slurm
> where they're already mounted.

To be honest on an HPC node it's the batch system that should be controlling 
the cgroups rather than systemd.

What would be ideal (if you can sacrifice the cores) would be to tell systemd 
to just use a single core for all its stuff and leave everything else 
available for Slurm to manage.

That way there's no OS jitter from system daemons running on the same cores as 
the applications themselves.

I know, I can dream.. ;-)

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Re: Getting systemd to not use cpuacct cgroup on RHEL 7.2

[Chris Samuel via luv-main]

On Mon, 21 Dec 2015 02:52:04 PM Jason White via luv-main wrote:

> While this doesn't directly answer your question, does anything on the
> following page provide a clue?
> https://wiki.archlinux.org/index.php/Slurm

Hmm, don't trust any page that links to the LLNL docs, they're really old & no 
longer apply to current versions, that page needs to be fixed to point to 
http://slurm.schedmd.com/ as that's where the developers are now (and yes, 
it's still GPL).

> This doesn't tell us how they worked around the issue. Do you have the Slurm
> unit file for systemd? This might contain the necessary ingredient, but
> that's just a guess on my part.

Yeah, I've got those (they're in the source distribution) but it is a bit more 
involved than that.  I've just got this email on the slurm-devel list that 
essentially confirms and expands on what Clinton mentioned:

http://permalink.gmane.org/gmane.comp.distributed.slurm.devel/9100

All the best,
Chris
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Re: Fixing the LUV list?

[Chris Samuel via luv-main]

On Sat, 19 Dec 2015 04:04:45 PM Anders Holmström via luv-main wrote:

> As mentioned it was on luv-talk.

That's fine for changes to luv-talk, but IMHO changes to luv-main should have 
been discussed on luv-main, where the actual subscribers are.

Thanks for the clarification, I went back and realised I'd misread Craig's 
email, I though he'd said it was discussed here but he was referring to the 
changes happening to luv-talk first and then luv-main.

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Re: Backups with rsync [Was: Is my root partition dying?]

[Chris Samuel via luv-main]

On Mon, 21 Dec 2015 11:25:29 AM Trent W. Buck via luv-main wrote:

> Or see btrfs/ZFS snapshots.  These operate per block rather than per
> inode, so should be more effective and less failure-prone in edge cases
> (hint, there's an upper limit on hard link count).

Yeah, I use both rsnapshot backups on ext4 and btrfs snapshots (both on 
external drives) and where I rsync with --inplace --no-whole-file for the 
btrfs side.

cheers,
Chris
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Getting systemd to not use cpuacct cgroup on RHEL 7.2

[Chris Samuel via luv-main]

/* No systemd religious wars please - thank you */

Hi folks,

I'm trying to get Slurm working on a RHEL7.2 system and I've hit an issue where
systemd is already using the cpuacct cgroup hierarchy and that prevents Slurm
from using it as it seems to be the one case where it can only be in use once.

I.e. having this mount create by systemd:

cgroup /sys/fs/cgroup/cpu,cpuacct cgroup 
rw,nosuid,nodev,noexec,relatime,cpuacct,cpu 0 0

causes:

12725 mount("cgroup", "/cgroup/cpuacct", "cgroup", 
MS_NOSUID|MS_NODEV|MS_NOEXEC, "cpuacct") = -1 EBUSY (Device or resource busy)

Anyone got any ideas on how to stop systemd from using it?

All the best,
Chris
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Re: hosting etc

[Chris Samuel via luv-main]

On Sat, 19 Dec 2015 07:22:35 PM Russell Coker via luv-main wrote:

> We are in the process of making other hosting arrangements.  One issue that
> is  yet to be discussed is where to host the lists, in the past Linux
> Australia offered to host lists for us and we may take them up on that
> offer if it's still available.

Their systems are in the same place..

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Re: Backups with rsync [Was: Is my root partition dying?]

[Chris Samuel via luv-main]

On Thu, 17 Dec 2015 11:06:10 PM Erik Christiansen via luv-main wrote:

> I'm not grokking the benefit of doing the rsync _and_ a "cp -al". I just
> include -aH in my rsync options, the -H to preserve hard links. Seems to
> work.

The idea is to have snapshots over time, rather than a single snapshot.  For 
instance as implemented in:

http://rsnapshot.org/

All the best,
Chris
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Fixing the LUV list?

[Chris Samuel via luv-main]

Hi folks,

I tried emailing the committee, but that just got moderated and I've not heard 
anything since, so I was wondering are was any progress on fix the LUV mailing 
list to not rewrite the From: header?

thanks,
Chris
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Re: Fixing the LUV list?

[Chris Samuel via luv-main]

On Sat, 5 Dec 2015 12:57:23 PM Brian May via luv-main wrote:

> First you need to convince the list administor to change it back.

This is the *only* email list I'm that has this crazy setup. I can't believe 
it's required.  Even the Beowulf list that I run, with over 1,500 members, 
doesn't need it.

> There was a long discussion on luv-talk

Wrong place to discuss it, IMHO.

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Re: changes to mailing list

[Chris Samuel via luv-main]

On Thu, 26 Nov 2015 09:08:50 AM Tony Langdon via luv-main wrote:

> Same result here.  Only Craig's posts don't allow me to reply to all.
> This function worked properly with your post just now, Erik.

That seems to be a Thunderbird bug, it works fine for both Craig and Eriks 
emails when I reply-all in Kmail.

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Re: Kernel 3.17 (and later) no longer allows bonding ppp devices

[Chris Samuel via luv-main]

On Mon, 16 Nov 2015 12:47:35 AM Toby Corkindale via luv-main wrote:

> d) Linux netdev mailing list pretty much ignored my attempts to get this
> sorted out, so I gave up, and will just quietly keep patching my own
> kernels.

Disappointed to hear that.. :-(

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