Sysadmin Mega Thread

mutation666 · January 20, 2021, 3:02pm

TheCakeIsNaOH · January 20, 2021, 11:50pm

Does anyone know the best way for a libvirt/qemu/kvm virtual machine to access an exposed port from docker on the host?

So I have a docker container with a port exposed:

ports:
    - '8080:8080'

I also have a virtual machine connected to an isolated virtual network,

I can ping 192.168.100.1 (ip of the host in the virtual network), and I can get to nginx on the host. But 192.168.100.1:8080 of the docker container does not load.

Edit:

Well, changing to the default network works, maybe “internal and host routing only” does not include docker containers. It is REALLY slow though, about 10 megabit. I can get over a gigabit from the container on a different machine, so it is definitly a software issue.

I am using a virtio device on the VM end, so I don’t think it is that.

SgtAwesomesauce · January 21, 2021, 1:27am

libvirt is not aware of docker, so it won’t count the docker veth devices.

Check your link speeds on all devices. Sometimes they need to be manually forced because dumb.

TheCakeIsNaOH · January 21, 2021, 1:33am

Showing 10 gigabit on the VM end, not sure how/if bridges have a connection speed, and if they how to check that.

SgtAwesomesauce · January 21, 2021, 1:34am

ehh bridges technically have a connection speed, but they’re happy to pass packets as fast as the computer is capable of doing.

But only having a connection speed in that they will negotiate with the vnic.

TheCakeIsNaOH · January 21, 2021, 1:38am

Well, the connection speed thing seems to have fixed itself, getting over 100 megabit now, which is around what I’d expect given the application.

Networking is probably my least favorite part of sysadmin type stuff.

SgtAwesomesauce · January 21, 2021, 1:46am

Don’t you love it when that stuff happens?

Stay well away from anyone who enjoys it.

oO.o · January 21, 2021, 3:08am

Shut up you need me

SgtAwesomesauce · January 21, 2021, 3:24am

psh, you have ssh and telnet. we can keep you caged for public safety.

oO.o · January 21, 2021, 6:05pm

Has anyone set up nextcloud with the ldap/ad backend before?

Nextcloud FreeNAS Plugin LDAP Broken? Software & Operating Systems

I’m trying to set up the nextcloud plugin in FreeNAS with the LDAP/AD backend. Initially I just want to get a simple bind over (no ssl), but it seems broken. [Screen Shot 2021-01-21 at 12.09.13] When I click detect port here, it just hangs. Same if I use the address of a specific dc. Nothing seems to happen if I fill out the rest of the information correctly either. Binds on other systems on the same subnet are working fine. [Screen Shot 2021-01-21 at 12.12.15] Save Credentials button has no effect, nor do any other buttons on this page. Nothing in the logs except some sql errors from yesterday from when it was initially set up. [Screen Shot 2021-01-21 at 12.14.15] All log levels are enabled: [Screen Shot 2021-01-21 at 12.14.41] php has the ldap module installed: [Screen Shot 2021-01-21 at 12.16.34] I’ve set the firewall to allow all traffic to the domain controllers from this subnet. I can ping the dcs, I can ssh into them from the nextcloud jail, etc. Time is sync’d and the dcs are set as the dns servers. Any ideas?

I remember trying it before and not running into any issues, so I suspect something is up with the FreeNAS plugin…

nx2l · January 21, 2021, 6:07pm

id be willing to try with freeipa… but i dont have freenas

oO.o · January 21, 2021, 6:11pm

I might try nextcloud in a vm to see if that magically works.

mutation666 · January 21, 2021, 6:22pm

Literally no one uses this (maybe like 15 years ago)

nx2l · January 21, 2021, 6:28pm

there are sadly lots of places that use it internally…

mutation666 · January 21, 2021, 6:29pm

(X)Doubt unless they dont have network people

nx2l · January 21, 2021, 6:31pm

I literally know a vendor that uses it b/c they do crazy shit with the filesystem and put stuff in weird places, which can break ssh ( on migration/software installs/etc) , and their fallback is to have telnet to get back in

mutation666 · January 21, 2021, 6:31pm

That sounds like server people doing stupid things not network

nx2l · January 21, 2021, 6:32pm

i am one of the server people and i want them to stop doing it.

mutation666 · January 21, 2021, 6:32pm

Tell the network people to block the traffic

oO.o · January 21, 2021, 6:47pm

Older Ubiquiti Edgeswitch firmwares had it on by default and you’ll still get one with that firmware on it from time to time. I have an expect script that telnets in, generates ssh keys, enables ssh and disables telnet.