August 2017 - Talk - lists.gtalug.org

war story: power failure makes CentOS system unbootable
by D. Hugh Redelmeier 30 Sep '22

30 Sep '22

tl;dr / spoiler: change fstab so that /boot/efi is not automatically mounted. See the recommendation at the end of this message. My gateway computer is a little PC running CentOS. It does not come back after a power failure. The reason (as best I can tell) is interesting and I think that I have a fix. My system is UEFI. It boots from a UEFI system partition, known as /boot/efi to Linux. If this gets corrupted, it won't boot. It is a VFAT partition. On my gateway (a Zotac Zbox RI321, a cute little box with two ethernet ports), the UEFI firmware apparently won't boot if the dirty bit is set in the system partition. CentOS normally runs with /boot/efi mounted. So when the system isn't shut down cleanly, the dirty bit will be on. Consequence: the system is not going to boot after a power failure. Odd observation 1: if I put a live Fedora 25 USB stick in the system and try to boot in this otherwise-unbootable state, CentOS boots from the main disk. So this really looks like a firmware bug/quirk. Odd observation 2: fsck doesn't seem to automatically fix the system partition. Once CentOS 7 booted, I dismounted /boot/efi and did an fsck on it. $ sudo fsck /dev/sda1 fsck from util-linux 2.23.2 fsck.fat 3.0.20 (12 Jun 2013) 0x25: Dirty bit is set. Fs was not properly unmounted and some data may be corrupt. 1) Remove dirty bit 2) No action ? 1 Leaving filesystem unchanged. /dev/sda1: 16 files, 2420/51145 clusters Googling got me to <https://www.centos.org/forums/viewtopic.php?t=50917> In particular, this advice seemed quite good: ==== recommendation ==== Two other changes I recommend for UEFI systems, to each OS's /etc/fstab. - For the /boot/efi mountpoint, add the mount options x-systemd.automount,noauto - Change fs_passno (last column) to a 1 or 2; the canonical fstab instructions suggest 2, but systemd treats 1 and 2 as the same. The first change means the EFI System partition will not be automatically read-write mounted at boot time; it's a bad idea this is the default because it puts the ESP at risk especially if ther are crashes, FAT has no journal and will therefore always be marked dirty in such a case; no other UEFI OS mounts the ESP by default. Second, if anything tries to access /boot/efi (read or write), systemd will automatically mount it, and because of the fs_passno 1 or 2, it will fsck it first and that fixes and clears the dirty bit in case it's set. Right now without these changes, it's just a matter of having the right number and bad timing of crashes to render the EFI System partition corrupt.

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Any Debian Developers here can help me sign my GPG key?
by tlugys.ats＠spamgourmet.com 26 Feb '18

26 Feb '18

Hi GTALUG members, Do we have any Debian Developers here? I am in the second step of becoming New Debian Maintainer process -- https://nm.debian.org/process/194 and now need to have my GPG key signed by a Debian member. I was directed to the THUG group (Toronto (GNU)/Hurd User Group) http://www.nongnu.org/thug/ but only to find that their listed email (thug(a)gnu.org) is no longer working. So I'm in a bad position now, and really hope that there is a Debian Developer here, or you know of, that can help me. I live in GTA, North York to be exactly. Any help can comfort my desperate heart. Thanks Antonio

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[GTALUG-Announce] Meeting on 12 September at 7:30pm
by hi＠gtalug.org 29 Aug '17

29 Aug '17

<http://gtalug.org/meeting/2017-09/> # xterm and Docker *xterms: State of Art 2017* with Christopher Browne Many of us "live" in xterms, and there have been some developments. This talk pokes a bit at: - The old, and what's still being developed - The new, and there ARE some interesting developments - A bit of the crazy! Want an xterm that simulates shakey old amber monitors? You got it! *Docker* with Greg Martyn TDA ## Location George Vari Engineering and Computing Centre 245 Church Street, Room 203 Ryerson University <http://goo.gl/maps/16oJ2> <http://www.openstreetmap.org/way/23447525> ## Schedule * 6:00 pm - Please discuss on the general mailing list (i.e. <talk(a)gtalug.org>) where you want to go for dinner. * 7:30 pm - Meeting and presentation. * 9:00 pm - After each meeting, a group of GTALUGers move to The Imperial Pub (54 Dundas St East) for refreshments and more socialising. # Code of Conduct We want a productive happy community that can welcome new ideas, improve every process every year, and foster collaboration between individuals with differing needs, interests and skills. We gain strength from diversity, and actively seek participation from those who enhance it. This code of conduct exists to ensure that diverse groups collaborate to mutual advantage and enjoyment. We will challenge prejudice that could jeopardise the participation of any person in the community. The Code of Conduct governs how we behave in public or in private whenever the Linux community will be judged by our actions. We expect it to be honoured by everyone who represents the community officially or informally, claims affiliation or participates directly. It applies to activities online or offline. We invite anybody to participate. Our community is open. Please read more about the GTALUG Code of Conduct here: <http://gtalug.org/about/code-of-conduct/>. If you have any questions, comments, or concerns about the GTALUG Code of Conduct please contact the GTALUG Board @ <board(a)gtalug.org>. --- GTALUG Announce mailing list announce(a)gtalug.org https://gtalug.org/mailman/listinfo/announce

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Re: [GTALUG] colour management
by Russell Reiter 27 Aug '17

27 Aug '17

On August 26, 2017 11:45:17 AM EDT, "Stewart C. Russell via talk" < talk(a)gtalug.org> wrote: >(subject changed from "Re: [GTALUG] Raspberry PI wifi problem") > >On 2017-08-25 03:49 PM, Russell via talk wrote: >> >> My biggest nice to have feature would be a comprehensive source of >ICC lookup tables for linux. > >If you're meaning for scanners, generic manufacturer ones are kind of >useless. Light sources age and shift, and so your generic calibration >becomes less and less useful. If you have to have one of these files, >dig about in the Windows or Mac driver package, as there's usually one >there. I just recently acquired Windows 10 with an hp mini I bought online. First personally purchased MS Windows OS ever. I jumped from DOS 6.2 to Linux for myself, leaving Windows to the business end of things. I learned M$ Windows stuff on other peoples dime. I'm kind of frugal that way. > >With an ICC target — Wolf Faust sells cheap but good ones from >http://www.targets.coloraid.de/ — it's easy to calibrate a scanner. >I've >always meant to > >a.) do a lightning talk on colour management; I'd find that interesting. I've never colour calibrated a scanner, never needed that kind of fine grained reproduction. > >b.) arrange a group buy of scanner targets. Wolf sells them *very* >cheap >if you're shipping more than one. > >I have a spare (stored in the dark, unused, technically expired but >good >enough) ITU target if anyone wants one. Wolf makes targets for the big >repro companies, so his stuff is good. He's also been writing printer >drivers since the early 1990s. > >You might also be surprised at what's living in /usr/share/color/icc >already … > >> I wouldn't have to stop cups to be able to scan with my MFU. > >Is your AIO networked, or connected via USB? cups tends to hog the USB, the problem for me, outside of the flimsy feed table which throws off alerts about itself, is that I have to manually trigger a udev event to be able to access the scanner. If I reboot and have forgotten to stop cups service and then try to scan with xsane, it cleans the print head and then the low colour tank indicator on the unit flashes, even though the tank is full. Simple Scan does nothing. If I just stop cups, and turn off and on the power, simple scan works poorly but, xsane can't find the device at all. I have to power it off by unplugging and then switch on again before xsane recognizes something. However the scan quality is very much higher. I think I have a couple of concurrent issues. One, there is something mysteriously funky about connecting USB 2.0 B male downstream to 3.0 female. Not necessarily in the hardware, Linux afaik doesn't report ink volume, MS will, so it looks like its more of a presentation layer issue. Ink volume is a kind of colour property report. I think that xsane start-scan command to the unit is being misinterpereted as clean head and report ink volume when cups service is running. The other thing is the modeswitching from printer to scanner, which I have kluged. At this point I could create a couple of system targets to stop cups before xsane starts and start cups if lpq is populated but, since this is a photo printer not in daily use, I keep the print daemon inactive. I scan much more than I print. There is a known issue with the infeed on Cannon Pixma. The fix is to remove the flimsy plate and flex it by hand to reshape it so the feed works consistantly. Rather than do that, I'll eventually replace it. This one was a Christmas gift to print photos from the holidays. The paperstops of the scan table are very precise and squared to the scan bed for one button photocopying of pictures on the bed, so no futzing with baseline registration when printing a scanned image. >whole >device over USB. xsane finds my networked Epson, but annoyingly all >drivers (perhaps the hardware itself) can only scan at 8 bpp. Well I would like a few more than 256 colours but in fact for my own day to day use that would probably be fine. I'm not a real shutterbug and I dont create a lot of personal/busines paper fallout at home. > > Stewart >--- >Talk Mailing List >talk(a)gtalug.org >https://gtalug.org/mailman/listinfo/talk

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Re: [GTALUG] Raspberry PI wifi problem
by John Moniz 26 Aug '17

26 Aug '17

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Raspberry PI wifi problem
by Evan Leibovitch 25 Aug '17

25 Aug '17

Hi all. Making networking run on Linux desktops has always been IMO one of the reasons why it's not caught on. Stuff just shouldn't be this hard. I have a RPi Model B running current Raspian, and a wifi dongle that claims to run on it. `lsusb` reports it as Bus 001 Device 004: ID 148f:7601 Ralink Technology, Corp. MT7601U Wireless Adapter and `usb-devices` says: T: Bus=01 Lev=02 Prnt=02 Port=01 Cnt=02 Dev#= 4 Spd=480 MxCh= 0 D: Ver= 2.01 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs= 1 P: Vendor=148f ProdID=7601 Rev=00.00 S: Manufacturer=MediaTek S: Product=802.11 n WLAN S: SerialNumber=1.0 C: #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=160mA I: If#= 0 Alt= 0 #EPs= 8 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none) Now... even though it says "Driver=(none)" on that last line, `lsmod` reports: Module Size Used by [...] mt7601u 86636 0 mac80211 650707 1 mt7601u cfg80211 525998 2 mac80211,mt7601u [...] snd_hwdep 6479 1 snd_usb_audio videodev 177702 3 uvcvideo,videobuf2_core,videobuf2_v4l2 snd_usbmidi_lib 22479 1 snd_usb_audio snd_rawmidi 23727 1 snd_usbmidi_lib media 28994 2 uvcvideo,videodev rfkill 21373 2 cfg80211 snd_seq_device 5266 1 snd_rawmidi snd_bcm2835 23131 0 snd_pcm 97825 2 snd_usb_audio,snd_bcm2835 snd_timer 22706 1 snd_pcm snd 68784 8 snd_hwdep,snd_usb_audio,snd_timer,snd_rawmidi,snd_usbmidi_lib,snd_seq_device,snd_bcm2835,snd_pcm bcm2835_gpiomem 3791 0 uio_pdrv_genirq 3718 0 uio 10166 1 uio_pdrv_genirq fixed 3029 0 ip_tables 12512 0 x_tables 20921 1 ip_tables ipv6 384391 18 So there is a module called mt7201u being loaded yet it's not seen as the associated driver to this card in usb-devices and it's definitely not showing in ifconfig or iwconfig. Any suggestions on what I'm missing is greatly appreciated. -- Evan Leibovitch Toronto, Canada Em: evan at telly dot org Sk: evanleibovitch Tw: el56

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Raspberry PI hdmi problem
by David Mason 25 Aug '17

25 Aug '17

Evan's post reminded me of a problem I have left on the back-burner for a year. I also have a RPI Model B that I bought as a media centre, but for that to work, it needs to go through my Pioneer receiver to my projector (because I have other sources and I need to switch among them). Unfortunately, that doesn't work, although it works if directly plugged in to the projector. I tried at the time to email someone at Raspberry, but never got a reply. When I saw Evan's post, it reminded me that I'd really like to get it working, and that somebody here might know something. Thanks ../Dave

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Re: [GTALUG] Spam is basically dead
by Stewart Russell 18 Aug '17

18 Aug '17

On 17 August 2017 at 12:54, David Collier-Brown <davec-b(a)rogers.com> wrote: > If they don't voluntarily agree to stop emailing me, I drop them into > spamcop form below: > > ^u^a^c... ^p and they get their corporate email provider flagged as a > spammer. > > This usually gets them told there will be a fine from the provider every > time they get blacklisted and have to appeal to be unlisted. That > motivates them wonderfully (;-)) > Please think twice before doing this. Spamcop, Spamhaus and the rest are little better than extortionists. If you have the unlucky coincidence to be on shared mail hosting with a blacklisted site, *your* mail can be blacklisted too. Tortuous interference can get very ugly (read $$$) in the courts. I had this happen at a former employer. We lost sales and communications for two days. The owner got in a foul mood, and I'm sure the last words of any well-intentioned but naive sysadmin that got within stabbing distance would have been: "We need our own mailserv...aaaargh!" cheers, Stewart

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Re: [GTALUG] Spam is basically dead
by Myles Braithwaite 👾 17 Aug '17

17 Aug '17

ac via talk wrote: > 1. Bounce when no rDNS (exim/postfix/sendmail/qmail - 2 second conf) Sometimes people don't have access to configure Reverse DNS (or PTR) as they are sending with a dynamic IP address. This isn't common but at least for GTALUG there are five or six people who host their email from their home on dynamic IP addresses. > 2. Use 10+ dnsbl with properly configured spamassasin (cache locally) - > with 2 (or more, or less) points per dnsbl listing > (five minutes copy & paste for exim/postfix) > -> dnsbl from here: http://multirbl.valli.org/ I stopped using SpamAssasin a while ago. I know use Rspamd, Rmilter, and OpenDMARC. I found SpamAssasin was letting in way to much spam and required way to much knowledge to run properly.

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Re: [GTALUG] Spam is basically dead
by Stewart C. Russell 17 Aug '17

17 Aug '17

On 2017-08-16 08:10 AM, ac via talk wrote: > > Six Golden Rules: ** Spam is basically dead... ** … if you run your own mailserver. This list's members are not representative of the general population. As a list mod, I can very much assure you that spam is in robust health indeed. Stewart

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