Tag: Fedora

Fedora: Finding Build Parameters for RPM

There have been a few times I’ve needed to make a custom build of an application — to enable some feature that the default build does not include or to use a newer version than is available in the package repository — and I always thought it would be really useful to know what the build parameters were. Turns out you can find how Fedora packages were build.

Go to https://koji.fedoraproject.org and search for the package

Locate ‘yours’ – the right version of the application and the right version of Fedora – and click on the package name

Scroll down to the “Logs” section – click on the “build.log” for the proper architecture

Here, you will see the entire log for building the RPM but part of that is building the application from source. You’ll be able to find the configuration and make parameters used in the build. As an example, I was trying to determine if Gerbera was build with the REUSEADDR flag (it was) and LIBUPNP disable-blocking-tcp-connections

https://kojipkgs.fedoraproject.org//packages/gerbera/2.0.0/1.fc39/data/logs/x86_64/build.log

In my particular case, I then had to find the libupnp package and see how that was built – they’ve got enable blocking tcp connections. Reusing the parameters from the RPM allows me to build packages that land files in “the right place” (or, rather, the place used in the Fedora package) and include any features they’ve included.

Samba – Address family not supported by protocol

After upgrading to Fedora 39, we started having problems with Samba falling over on startup. The server has IPv6 disabled, and (evidently) something is not happy about that. I guess we could enable IPv6, but we don’t really need it.

Adding the following to lines to the GLOBAL section of the smb.conf file and restarting samba sorted it:

bind interfaces only = yes
interfaces = lo eth0

 

Feb 11 06:26:01 systemd[1]: Started smb.service – Samba SMB Daemon.
Feb 11 06:26:01 smbd[1109]: [2024/02/11 06:26:01.285076, 0] ../../source3/smbd/server.c:1091(smbd_open_one_socket)
Feb 11 06:26:01 smbd[1109]: smbd_open_one_socket: open_socket_in failed: Address family not supported by protocol
Feb 11 06:26:01 smbd[1109]: [2024/02/11 06:26:01.290022, 0] ../../source3/smbd/server.c:1091(smbd_open_one_socket)
Feb 11 06:26:01 smbd[1109]: smbd_open_one_socket: open_socket_in failed: Address family not supported by protocol
Feb 11 08:01:43 systemd[1]: Stopping smb.service – Samba SMB Daemon…
Feb 11 08:01:43 systemd[1]: smb.service: Deactivated successfully.
Feb 11 08:01:43 systemd[1]: Stopped smb.service – Samba SMB Daemon.

Updating Fedora — System Boots to Grub Error After Update

If you film the boot sequence and look frame by frame, you’ll see that it very briefly flashes a TPM error

error: ../../grub-core/commands/efi/tpm.c:150:unknown TPM error.

 

From what I’ve been able to glean, this secure boot stuff works off of signatures. Microsoft has signatures in BIOS. Everyone else kind of inserts their keys on the fly … so you can run out of space to save these keys and be unable to boot. To work around this, every time an update gets us over the limit, we go into the secure boot DBX management menu and reset the “Forbidden Signatures” from factory default. This is 13 keys instead of 373, and the OS is able to do it’s “thing” and boot.

 

And I’m actually writing this down this time because I had spent a lot of time researching this last time Scott’s laptop failed to boot and dumped out to a grub menu. This time, I kinda know what we did and why but lost a lot of the details.

Mounting DD Raw Image File

And a final note from my disaster recovery adventure — I had to use ddrescue to copy as much data from a corrupted drive as possible (ddrescue /dev/sdb /mnt/vms/rescue/backup.raw –try-again –force –verbose) — once I had the image, what do you do with it? Fortunately, you can mount a dd file and copy data from it. 

# Mounting DD image
2023-04-17 23:54:01 [root@fedora /]# kpartx -l backup.raw
loop0p1 : 0 716800 /dev/loop0 2048
loop0p2 : 0 438835200 /dev/loop0 718848

2023-04-17 23:55:08 [root@fedora /]# mount /dev/mapper/loop0p2 /mnt/recovery/ -o loop,ro
mount: /mnt/recovery: cannot mount /dev/loop1 read-only.
       dmesg(1) may have more information after failed mount system call.

2023-04-17 23:55:10 [root@fedora /]# mount /dev/mapper/loop0p2 /mnt/recovery/ -o loop,ro,norecovery

2023-04-18 00:01:03 [root@fedora /]# ll /mnt/recovery/
total 205G
drwxr-xr-x  2 root root  213 Jul 14  2021 .
drwxr-xr-x. 8 root root  123 Apr 17 22:38 ..
-rw-r--r--. 1 root root 127G Apr 17 20:35 ExchangeServer.qcow2
-rw-r--r--. 1 qemu qemu  10G Apr 17 21:42 Fedora.qcow2
-rw-r--r--. 1 qemu qemu  15G Apr 17 14:05 FedoraVarMountPoint.qcow2

Mounting a QCOW File

We had a power outage on Monday that took out the drive that holds our VMs. There are backups, but the backup drive copies had superblock errors and all sorts of issues. To recover our data, I learned all sorts of new things — firstly that you can mount a QCOW file and copy data out. First, you have to connect a network block device to the file. Once it is connected, you can use fdisk to list the partitions on the drive and mount those partitions. In this example, I had a partition called nbd0p1 that I mounted to /mnt/data_recovery

modprobe nbd max_part=2
qemu-nbd --connect=/dev/nbd0 /path/to/server_file.qcow2
fdisk /dev/nbd0 -l
mount /dev/nbd0p1 /mnt/data_recovery

Once you are done, unmount it and disconnect from the network block device. 

umount /mnt/data_recovery
qemu-nbd --disconnect /dev/nbd0
rmmod nbd

KDE Dolphin — Unable to Move Files and Folders

Scott was trying to move some backup files from /a/path/to/backup to /a/path/to-a-different/backup — he’s using Dolphin & has a tab open to each of the folders in question. He chown’d /a/path to his account, chmod’d /a/path so user can read and write. But using the copy/paste option … nothing happens.

I came across a few old (and closed) bugs that seemed to produce errors in this same situation — but the reporters were able to perform their copy/move operations when they used the same tab instead of having one folder open in each tab. It worked … inexplicable, but we have success!