Re: [CentOS] Retrieving files from dd backup
On 11/26/2020 07:19 PM, H wrote: > On 11/26/2020 05:27 PM, Leon Fauster via CentOS wrote: >> Am 26.11.20 um 20:10 schrieb H: >>> Running CentOS 7 I have a previously combined backup of a disk with three >>> partitions using dd. I now need to restore one single file from this backup >>> and after perusing the internet, specifically >>> https://unix.stackexchange.com/questions/31669/is-it-possible-to-mount-a-gzip-compressed-dd-image-on-the-fly, >>> I have done the following: >>> >>> - installed squashfs-tools >>> >>> - installed kpartx >>> >>> - made a squash image of the dd backup and mounted it >>> >>> - used kpartx to create devices for the three partitions under >>> /dev/mapper/loopNpP >>> >>> - I can now mount the first partition, which is the EFI partition, and >>> access it >>> >>> - the second partition, the boot partition, fails to mount since it has the >>> same UUID as the disk I am using in the computer, and of which it is an >>> earlier dd backup. Since I am not interested in the boot partition - at >>> least not right now - I moved on. >>> >>> - I am, however, interested in the third partition which is LUKS encrypted. >>> Running 'cryptsetup luksOpen /dev/sda3 my_encrypted_volume' I can decrypt >>> it with the password >>> >>> - trying to mount the decrypted version with 'mount >>> /dev/mapper/my_encrypted_volume /media/my_device' results in a failure >>> message 'mount: unknown filesystem type 'LVM2_member' >>> >>> - another website, >>> https://askubuntu.com/questions/766048/mount-unknown-filesystem-type-lvm2-member, >>> suggests I could run vgdisplay to get the UUID and then rename it using >>> vgrename >>> >>> But, vgdisplay shows only one vg and I am afraid to rename the VG UUID >>> shown by vgdisplay since it might refer to the VG currently in use... >>> >>> Does anyone have any insight or suggestions into the above and how to >>> proceed while being absolutely certain I will not be messing up the running >>> part of the system? >>> >> IIRC: Activate the LVM via: vgchange -a y >> >> and mount the logical volume (LV). >> >> LV can be listed with lvs. The device nodes are under /dev/mapper ... >> >> -- >> Leon >> >> >> >> >> >> ___ >> CentOS mailing list >> CentOS@centos.org >> https://lists.centos.org/mailman/listinfo/centos > OK, I am looking at > https://www.cyberciti.biz/faq/linux-mount-an-lvm-volume-partition-command/. A > couple of follow-up questions: > > - Would activating the LVM with 'vgchange -a y' make any changes, or create > any potential issues, with the system already running? > > - How do I know that the output from 'vgdisplay' refers to this 'new' VG and > not VGs on the running system? > > - To mount the VG, I would have to run: > > -- 'vgscan' > > -- make directory for mounting > > -- 'mount...' to mount the VG > > Is that correct? And it would not create any issues with the running system? > > Thank you in advance. > > ___ > CentOS mailing list > CentOS@centos.org > https://lists.centos.org/mailman/listinfo/centos OK, finally had time to delve into this and become a LVM expert (ha!) I got it working and can retrieve files from old dd images, both unencrypted and LUKS encrypted. Note that I did this on another computer than the dd images were made from to avoid UUID conflicts. However, a couple of questions: Section 1: I had no problems mounting and accessing the files for the boot partition but since the home partition is a "LVM2_member", I had to go through some extra steps such as: "vgimportclone --basevgname -i /dev/mapper/mev" (the latter location is an arbitrary name chosen by me) This results in error message: "Error writing device /dev/mapper/mev at 4096 length 512. bcache_invalidate: block (6, 0) still dirty Failed to write mda header to /dev/mapper/mev fd -1" Question 1: - What does this error message really mean? Is this something I ought to fix (although I blithely continued as below...) Section 2: However, after running lvscan, vgchange -ay, ls -lh /dev/mapper to find out which /dev/dm-* to mount (/dev/dm-7) in my case: "mount -o ro,loop /dev/dm-7 mtb3" (the latter again is a mount point arbitrarily chosen by me) Results in another error message about a missing superblock which could be corrected by: "mount -o ro,loop,norecovery /dev/dm-7 mtb3" I was then able to recover the couple of files I needed. Question 2: - Should I do something different when eventually mounting to avoid the error message about a missing superblock? Or is there something wrong with the disk partition I had copied by dd? Looking forward to insight by those more knowledgeable than myself. Many thanks. ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] Logitech C922 webcam
On 11/13/2020 12:46 PM, H wrote: > On 11/13/2020 12:40 PM, H wrote: >> On 10/02/2020 07:38 AM, H wrote: >>> On October 1, 2020 11:58:11 AM EDT, Bruce Ferrell >>> wrote: On 9/30/20 8:52 AM, H wrote: > 00:14.0 USB controller: Intel Corporation 200 Series/Z370 Chipset Family USB 3.0 xHCI Controller My system has these: 00:14.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB xHCI (rev 05) 00:1a.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #2 (rev 05) 00:1d.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #1 (rev 05) lspci -s 00:14.0 -v 00:14.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB xHCI (rev 05) (prog-if 30 [XHCI]) Subsystem: ASUSTeK Computer Inc. Device 201f Flags: bus master, medium devsel, latency 0, IRQ 25 Memory at dd60 (64-bit, non-prefetchable) [size=64K] Capabilities: [70] Power Management version 2 Capabilities: [80] MSI: Enable+ Count=1/8 Maskable- 64bit+ Kernel driver in use: xhci_hcd Kernel modules: xhci_pci lspci -s 00:1a.0 -v 00:1a.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #2 (rev 05) (prog-if 20 [EHCI]) Subsystem: ASUSTeK Computer Inc. Device 201f Flags: bus master, medium devsel, latency 0, IRQ 16 Memory at dd618000 (32-bit, non-prefetchable) [size=1K] Capabilities: [50] Power Management version 2 Capabilities: [58] Debug port: BAR=1 offset=00a0 Capabilities: [98] PCI Advanced Features Kernel driver in use: ehci-pci Kernel modules: ehci_pci lspci -s 00:1d.0 -v 00:1d.0 USB controller: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #1 (rev 05) (prog-if 20 [EHCI]) Subsystem: ASUSTeK Computer Inc. Device 201f Flags: bus master, medium devsel, latency 0, IRQ 23 Memory at dd617000 (32-bit, non-prefetchable) [size=1K] Capabilities: [50] Power Management version 2 Capabilities: [58] Debug port: BAR=1 offset=00a0 Capabilities: [98] PCI Advanced Features Kernel driver in use: ehci-pci Kernel modules: ehci_pci These are my kernel modules: lsmod | grep usb btusb 53248 0 btrtl 16384 1 btusb btbcm 16384 1 btusb btintel 20480 1 btusb bluetooth 589824 41 btrtl,btintel,bnep,btbcm,rfcomm,btusb snd_usb_audio 278528 1 snd_usbmidi_lib 36864 1 snd_usb_audio snd_hwdep 16384 2 snd_hda_codec,snd_usb_audio snd_rawmidi 40960 1 snd_usbmidi_lib snd_pcm 143360 5 snd_hda_intel,snd_hda_codec,snd_usb_audio,snd_hda_core,snd_hda_codec_hdmi snd 98304 23 snd_hda_intel,snd_hwdep,snd_seq,snd_hda_codec,snd_usb_audio,snd_timer,snd_rawmidi,snd_hda_codec_hdmi,snd_hda_codec_generic,snd_usbmidi_lib,snd_seq_device,snd_hda_codec_realtek,snd_pcm usbhid 57344 0 usbcore 290816 9 uvcvideo,usbhid,snd_usb_audio,ehci_hcd,xhci_pci,snd_usbmidi_lib,btusb,xhci_hcd,ehci_pci This line is important: usbcore 290816 9 uvcvideo,usbhid,snd_usb_audio,ehci_hcd,xhci_pci,snd_usbmidi_lib,btusb,xhci_hcd,ehci_pci Notice the last two entries: xhci_hcd and ehci_pci Those correspond to: for my two usb 2 controllers: Kernel driver in use: xhci_hcd Kernel modules: xhci_pci for my single usb 3 controller: Kernel driver in use: xhci_hcd Kernel modules: xhci_pci >>> >from your lspci: 00:14.0 USB controller: Intel Corporation 200 Series/Z370 Chipset Family USB 3.0 xHCI Controller This is the sole USB controller in your system and it's a USB 3 controller so... in your case let's do: sudo lspci -s 00:14.0 -v then try: sudo modprobe usbcore and repeat: sudo lspci -s 00:14.0 -v see if the Kernel driver/module lines change. If they do, plug the camera in and check for it to be recognized in lsusb ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos >>> Thank you. Unfortunately I will not have access to this computer for some >>> time, will let you know when I can try what you suggest. >>> ___ >>> CentOS mailing list >>> CentOS@centos.org >>>
Re: [CentOS] Selecting a Desktop
gdm allows that. Click the little gear beside the login button and select the desktop you want. (The little gear shows up only when more than one desktop is actually installed and available for use.) On Sat, 05 Dec 2020 15:37:05 -0800 david wrote: > Folks > > Some of my users like GNOME, some like XFCE, and there's even a MATE > lover out there. And some would like to change desktops from time to > time. Is there some way to allow a user to choose her own > desktop? I can envision at least two ways this might be done: > > 1) Present a user with a command-line login, and have a program > (let's call it 'gui') so the user could type in "gui g" for gnome, > "gui m' for mate, and so on. > > 2) Present a uses with a gui login-in screen, which also includes a > desktop selector. > > Of course, it would only offer those desktops which are installed. > > Is there such? > > Gui-Confused > > David > > ___ > CentOS mailing list > CentOS@centos.org > https://lists.centos.org/mailman/listinfo/centos > -- MELVILLE THEATRE ~ Real D 3D Digital Cinema ~ www.melvilletheatre.com ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
[CentOS] Selecting a Desktop
Folks Some of my users like GNOME, some like XFCE, and there's even a MATE lover out there. And some would like to change desktops from time to time. Is there some way to allow a user to choose her own desktop? I can envision at least two ways this might be done: 1) Present a user with a command-line login, and have a program (let's call it 'gui') so the user could type in "gui g" for gnome, "gui m' for mate, and so on. 2) Present a uses with a gui login-in screen, which also includes a desktop selector. Of course, it would only offer those desktops which are installed. Is there such? Gui-Confused David ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] CentOS 8.2: error running non-shared postrotate script for /var/log/mysql/mysqld.log
Am 05.12.20 um 15:35 schrieb Alexander Farber: Hello fellow CentOS users! I have installed CentOS 8.2.2004 with the following packages: mysql-common-8.0.21-1.module_el8.2.0+493+63b41e36.x86_64 mysql-8.0.21-1.module_el8.2.0+493+63b41e36.x86_64 mysql-errmsg-8.0.21-1.module_el8.2.0+493+63b41e36.x86_64 mysql-server-8.0.21-1.module_el8.2.0+493+63b41e36.x86_64 Then I have run mysql_secure_installation and among other things set the root password for MySQL As result I am greeted with the following anachron mail every morning: /etc/cron.daily/logrotate: mysqladmin: connect to server at 'localhost' failed error: 'Access denied for user 'root'@'localhost' (using password: NO)' error: error running non-shared postrotate script for /var/log/mysql/mysqld.log of '/var/log/mysql/mysqld.log ' I understand that the reason is me having set the root password for MySQL. But my question is how to provide the password to postrotate without disclosing it too much? Other than that the MySQL works well, I use it to host 3 Wordpress websites at my CentOS 8 Linux server (haproxy -> Jetty x 3 -> FastCGI -> php-fpm -> Wordpress -> MySQL) Greetings from Germany Alex Hallo Alex, take a look into /etc/logrotate.d/mysqld -- Leon ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
[CentOS] CentOS 8.2: error running non-shared postrotate script for /var/log/mysql/mysqld.log
Hello fellow CentOS users! I have installed CentOS 8.2.2004 with the following packages: mysql-common-8.0.21-1.module_el8.2.0+493+63b41e36.x86_64 mysql-8.0.21-1.module_el8.2.0+493+63b41e36.x86_64 mysql-errmsg-8.0.21-1.module_el8.2.0+493+63b41e36.x86_64 mysql-server-8.0.21-1.module_el8.2.0+493+63b41e36.x86_64 Then I have run mysql_secure_installation and among other things set the root password for MySQL As result I am greeted with the following anachron mail every morning: /etc/cron.daily/logrotate: mysqladmin: connect to server at 'localhost' failed error: 'Access denied for user 'root'@'localhost' (using password: NO)' error: error running non-shared postrotate script for /var/log/mysql/mysqld.log of '/var/log/mysql/mysqld.log ' I understand that the reason is me having set the root password for MySQL. But my question is how to provide the password to postrotate without disclosing it too much? Other than that the MySQL works well, I use it to host 3 Wordpress websites at my CentOS 8 Linux server (haproxy -> Jetty x 3 -> FastCGI -> php-fpm -> Wordpress -> MySQL) Greetings from Germany Alex ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
Re: [CentOS] EFI System Partition on RAID 1 array
Le 05/12/2020 à 13:47, Nicolas Kovacs a écrit : > # mdadm --create /dev/md/EFI --level=1 --raid-devices=2 \ > --metadata=1.2 /dev/sda1 /dev/sdb1 I'll answer that myself, since I just found the solution to my problem after searching for hours. Turns out the EFI partition needs to be created with --metadata=1.0 instead of --metadata=1.0: # mdadm --create /dev/md/EFI --level=1 --raid-devices=2 \ --metadata=1.0 /dev/sda1 /dev/sdb1 Boots fine now. Cheers, Niki -- Microlinux - Solutions informatiques durables 7, place de l'église - 30730 Montpezat Site : https://www.microlinux.fr Blog : https://blog.microlinux.fr Mail : i...@microlinux.fr Tél. : 04 66 63 10 32 Mob. : 06 51 80 12 12 ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
[CentOS] EFI System Partition on RAID 1 array
Hi, I'm currently writing a little documentation on how to install CentOS 7 on manually partitioned disks, e. g. boot in Rescue Mode first, partition using fdisk or gdisk, reboot, start the installer and use the installer to format these partitions. I have a total of 9 (3 x 3) situations: * single disk (BIOS+MBR, BIOS+GPT, UEFI) * RAID 1 on 2 disks (BIOS+MBR, BIOS+GPT, UEFI) * RAID 6 on 4 disks (BIOS+ BR, BIOS+GPT, UEFI) Everything works fine so far and I've completed seven out of nine of these setups. But right now I'm stuck with a problem on how to manually setup RAID 1 with UEFI. Here's what I do. Fire up gdisk on /dev/sda. Create 4 RAID partitions (FD00): * 200 MB for /dev/md/EFI * 500 MB for /dev/md/boot * 4 GB for /dev/md/swap * 55 MB for /dev/md/root Create the RAID arrays: # mdadm --create /dev/md/EFI --level=1 --raid-devices=2 \ --metadata=1.2 /dev/sda1 /dev/sdb1 mdadm: array /dev/md/boot started # mdadm --create /dev/md/boot --level=1 --raid-devices=2 \ --metadata=1.2 /dev/sda2 /dev/sdb2 mdadm: array /dev/md/boot started # mdadm --create /dev/md/swap --level=1 --raid-devices=2 \ --metadata=1.2 /dev/sda3 /dev/sdb3 mdadm: array /dev/md/swap started # mdadm --create /dev/md/root --level=1 --raid-devices=2 \ --metadata=1.2 /dev/sda4 /dev/sdb4 mdadm: array /dev/md/root started And then I reboot, fire up the installer and assign these RAID arrays respectively to the EFI system partition as well as /boot, swap and /. Unfortunately I won't even reach the GRUB menu on boot. Only thing I get after the initial reboot is the EFI shell. Now I've tried this again, this time partitioning *and* formating using Anaconda. * one mountpoint for /boot/efi (RAID 1) * one mountpoint for /boot (RAID 1) * one mountpoint for swap (RAID 1) * one mountpoint for / (RAID 1) After the initial reboot, everything works fine. EFI on a RAID 1 array apparently works. So what am I missing and/or doing wrong in my manual setup? Cheers, Niki -- Microlinux - Solutions informatiques durables 7, place de l'église - 30730 Montpezat Site : https://www.microlinux.fr Blog : https://blog.microlinux.fr Mail : i...@microlinux.fr Tél. : 04 66 63 10 32 Mob. : 06 51 80 12 12 ___ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
