October 2018 - 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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Dinner tonight?
by David Collier-Brown 13 Nov '18

13 Nov '18

What's the current state of thought??? https://wiki.gtalug.org/pre-meeting_dinner -- David Collier-Brown, | Always do right. This will gratify System Programmer and Author | some people and astonish the rest davecb(a)spamcop.net | -- Mark Twain

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IBM Acquires Red Hat for $34B | News & Opinion | PCMag.com
by James Knott 07 Nov '18

07 Nov '18

IIRC, IBM had done a lot of work with SUSE in the past. https://www.pcmag.com/news/364649/ibm-acquires-red-hat-for-34b?utm_source=e…

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Backups with Bacula
by Tony Fernandez 31 Oct '18

31 Oct '18

Hi All, I just recently joined your group and was hoping for some insight or advise on building a backup solution. My question is related to Bacula on FreeNAS. I hope it's ok that I ask if not I understand. ==Background== We run a mixed environment (Windows and Linux). I've been slowly moving services that we run over to Linux wherever possible however I've run into an issue with our existing backup server. It is a Microsoft product. I'm not looking for help on it, instead I am looking for advise on using bacula. I've configured Bacula and have it working successfully and I like how I can deploy agents onto my servers to handle backups. I love the distributed achitecture. So my question: I'd like to use FreeNAS as our StorageDaemon (sd) going forward. I'd also like to do remote offsite backups by either rsyncing files over to a remote server or by getting FreeNAS to backup to an external HDD that I rotate weekly. ==Questions== Does anyone see any issues with this? What do you think about the HDD rotation? Thanks, Tony

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USB-C port was Aging Dell monitor (U3011)
by Michael Hill 31 Oct '18

31 Oct '18

On Sat, Mar 10, 2018 at 12:02 PM D. Hugh Redelmeier via talk <talk(a)gtalug.org> wrote: > According to > <http://www.dell.com/ed/business/p/dell-u3011/pd> > the monitor has > > DisplayPort, audio connectors (supports 5.1 channel audio > connection), two HDMI 1.3 and two DVI-D connectors with > High-Bandwidth Digital Copy Protection (HDCP). > > So the right way of connecting to a T450 should be DisplayPort to > DisplayPort. I've switched out the ThinkPad for a T480, which has *no* DisplayPort connector but brings back HDMI (lower resolution with the Dell monitor) and forces me to spend seventy bucks on a new cable (USB-C to DisplayPort). After the screen blanks, the monitor refuses to wake up. Sometimes, corrupt images (very gradually) appear in bands. When the monitor is asleep, Fedora thinks it's still there and leaves open windows on it, completely inaccessible. Powering it off and on does nothing, and it needs to be unplugged/reconnected. Am I missing a BIOS setting? (There were many that needed to be set initially.) Is this a driver problem or should I file a bug? Happens on Xorg and Wayland. Mike

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[GTALUG-Announce] Results of Elections
by Bill Thanis 27 Oct '18

27 Oct '18

My apologize for taking this long, but the results of the election are as follows: Scott Sullivan, Evan Leibovitch, and Gordon Chillcott. All were voted in by acclimation as no one else wished to run. Returing Officer: Bill Thanis --- GTALUG Announce mailing list announce(a)gtalug.org https://gtalug.org/mailman/listinfo/announce

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Various Tech looking for Good Homes
by Scott Sullivan 25 Oct '18

25 Oct '18

I have the following items for sale. I just don't have a use for them anymore, and would like to give this community first crack. Contact me off-list if your interested or have questions. ACER Aspire easyStore H340 * Intel Atom 230, 2GB RAM, No Drives * Includes added Compatible Graphics card, to make linux installs easy. https://revident.net/images/IMG_20181025_204544.jpg https://revident.net/images/IMG_20181025_204607.jpg [$80] Lenovo Thinkpad Ultra Dock * Power Supply and Original Keys included. https://revident.net/images/IMG_20181025_204034.jpg https://revident.net/images/IMG_20181025_204046.jpg https://revident.net/images/IMG_20181025_204232.jpg [$160] APC Back-UPS ES 350 * Battery will need to be replaced. https://revident.net/images/IMG_20181025_203922.jpg [$15] StarTech 2.5" Hotswap Bay, Expansion Card slot mount. * Used to add rear I/O access SATA drives, good for space constrained cases. https://revident.net/images/IMG_20181025_204650.jpg [$25 for all three] GnuBee PC2 NAS Deluxe Kit * Never used, bought for a purpose that wasn't ultimately needed. * BONUS: 6x 750GB Seagate ST3750640AS, free with purchase. * All drives have passed a recent badblocks run. https://revident.net/images/IMG_20181025_205118.jpg https://revident.net/images/IMG_20181025_205125.jpg https://www.crowdsupply.com/gnubee/personal-cloud-2 [$260] -- Scott Sullivan

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BIOS: Duplicate (3) Boot Drive Entries
by Stephen 23 Oct '18

23 Oct '18

The entries are all for the same SSD drive. Do I have have GRUB installed three times? From I boot nicely into Ubuntu 18.04 The other two stick on GRUB and say no OS found. How do I fix this? Thank you! -- Stephen

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Practical Use of GRUB's DSL: With the examples inexplicably left out of the GRUB documentation
by Giles Orr 16 Oct '18

16 Oct '18

I've finally released a document I've been working on for a while: "Practical Use of GRUB's DSL: With the examples inexplicably left out of the GRUB documentation" ( https://www.gilesorr.com/grubdsl/ ) Daniel did the editing, and set me on this path in the first place with his own interest in GRUB. The GRUB DSL is somewhat similar to an older version of a Linux shell, but documentation of its functionality online is poor to non-existent. Don't get me wrong: GRUB has a lot of documentation of individual commands, but how you can assemble them into useful scripts is barely documented at all. (Yup, its an uncommon application realm.) My greatest frustration with GRUB's DSL is the lack of redirection and pipes (I understand why they're not there - but it would be nice to have them). I hope this is helpful to someone! ----- As a technical side note, I learned the basics of LaTeX in an attempt to create this document in that language (I'd been wanting to learn it for years). LaTeX is supposed to be able to generate not only PostScript and PDF, but also HTML. But it turns out the HTML generator isn't nearly as well maintained as the PDF generator, and in the end I could find no way to implement my code examples in such a way that the HTML generator wouldn't fail on them. I also found the language unnecessarily complex for what I was trying to achieve and ultimately switched to raw HTML (which you see above). LaTeX may have been a poor choice. :-) -- Giles https://www.gilesorr.com/ gilesorr(a)gmail.com

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[GTALUG-Announce] Special Event: Seatbelts and Airbags for Bash w/ Michael Potter
by hi＠gtalug.org 16 Oct '18

16 Oct '18

# Special Event: Seatbelts and Airbags for Bash w/ Michael Potter https://www.eventbrite.ca/e/seatbelts-and-airbags-for-bash-tickets-51177497… ## Date and Time Wed, 17 October 2018 6:45 PM – 9:00 PM EDT # Location Hacklab.TO 1266 Queen Street West Suite #6 Toronto, Ontario M6K 1L3 # Abstract: This presentation will focus on the underutilized features of bash that are critical to building production quality scripts. Demos will show you how to turn on options and error trapping that expose the hidden time bombs in the code. Turning these features on should be considered a requirement, much like turning on “strict” and “warnings” is considered a requirement for Perl programs. Also, as much of the bash syntax has become outdated, the presentation will explain which syntax is best to use and which syntax to avoid. Knowledge of any of the common UNIX scripting languages will be sufficient to understand the presentation and script authors at all proficiency levels should find value in attending. Although the presentation does not address differences between Korn shell and bash, much of what will be discussed also applies to Korn shell. # Bio: Michael Potter is a long time UNIX user and C developer and more recently a consultant to insurance companies. He is a proponent of strongly typed languages which inspired him to try to "fix" bash by using its underutilized features to make it more reliable. Please arrive early to be seated, presentation will start at 7pm sharp. --- GTALUG Announce mailing list announce(a)gtalug.org https://gtalug.org/mailman/listinfo/announce

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