Category: Technology

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.

Tableau Error After Upgrading to 2023.3

I started upgrading our Tableau servers to 2023.3 this week. Several dashboards no longer rendered after the upgrade — throwing an error “TableauException: Incorrect data type real, getting expected integer type.” … resetting or not resetting the view did not help.

This is evidently a known issue (although the documentation prior to my reporting the issue seemed to go out of its way to say it is just the cloud platform being impacted)

https://issues.salesforce.com/issue/a028c00000iwtkXAAQ/~
https://kb.tableau.com/articles/Issue/error-incorrect-data-type-real-getting-expected-integer-type-occurs-intermittently-during-view-rendering

Both the server and desktop client are impacted — and, unlike their documentation that says it is intermittent? Not all workbooks are impacted, but the ones that are? A broken workbook is broken and will not render for anyone, anywhere, any time.

There is a workaround:

Server:
tsm configuration set -k features.EnableLogicalQueryBatchProcessor -v false
tsm pending-changes apply

Desktop:
“\Program Files\Tableau\Tableau 2023.3\bin\tableau.exe” -DOverride=EnableLogicalQueryBatchProcessor:off

Azure DevOps Maven Feed — Deleted Package

Someone deleted one of the packages from the Azure DevOps Maven feed … figured it would be easy enough to just re-publish the package. And they got an error:

409 Conflict – The version 1.2.3 of package.example.com has been deleted. It cannot be restored or pushed. (DevOps Activity ID: E7E4DEB1551D) -> [Help 1]

There’s some not-outlandish logic behind it because they don’t want half of the people to have this version 1.2.3 and the other half to get that version 1.2.3 … if it’s your code, just make it version 1.2.4. Unfortunately, this logic doesn’t hold up well when you’re publishing someone else’s package. Not like I can say “oops, we’ll use 23.13 now”. But you can restore deleted packages — from the feed, go into the recycle bin

Check off the packages that were deleted in error & restore them

 

ISC Bind 9.18 and Windows DNS

After upgrading all of our Linux hosts to Fedora 39, we are running ISC bind 9.18.21 … and it seems the ISC folks are finally done with Microsoft’s “kinda sorta RFC compliance”. Instead of just working around Windows DNS servers having some quirks … they now fail to AXFR the domain.

Fortunately, you can tell bind to stop doing edns ‘stuff‘ by adding a server{} section to named.conf — this gives the server some instructions on how to communicate with the listed server. When bind is no longer trying to do edns “stuff”, Windows doesn’t have an opportunity to provide a bad response, so the AXFR doesn’t fail.

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.

Python: Listing XML tags

I was having a lot of trouble using find/findall when parsing an XML document — turns out the namespace prefixed the tag name … so I needed to find {http://maven.apache.org/POM/4.0.0}groupId instead of just groupId

How do you figure that out? Quickest way, for me, was just to print out all of the tag names.

from lxml import etree
# Load POM XML into tree
tree = etree.parse( strXMLFile )

# # List all element names in XML document
for element in tree.iter():
     print(element.tag)

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.