Note to self – when trying to stop the continued requests for reboots to install pending updates in Windows Update, one of the go-to things to check is the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate\Auto Update\RebootRequired
Remember, don’t just delete the contents of this key, delete the actual key itself!
After updating anything to use systemd-235 NIS logins either don’t work at all (usually for GUI logins), or take a long time to login (console or ssh, sometimes). The culprit is a line in the systemd-logind.service:
IPAddressDeny=any
This sandboxes the service and doesn’t allow it to talk to the network. Unfortunately this affects nis lookups done via the glibc NSS API. See the links at https://github.com/systemd/systemd/pull/7343
The quick solution is to turn off the sandboxing, either by commenting out or changing the line in systemd-logind.service, or creating a drop-in snippet that overrides it. This can be done by creating a file /etc/systemd/system/systemd-logind.service.d/IPAddress_clear.conf with the contents:
As per this bug:
Debian Bug report logs – #852323
The Debian 9 installer (up to v9.5 at least) does not always configure GRUB to find the boot partition using UUID, but leaves it pointing to /dev/sdb or whatever. This can be a problem if you change disks in the system. In particular, if you install from a USB stick and then remove it when the system reboots after the install this can change the disk /dev id. The result is a unbootable system. This can be a bit fiddly to fix (although the first thing that’s always worth trying is to reverse the changes you made and see if it boots, e.g. plug the install USB stick back in to the same usb slot).
Ubuntu 18.04 has switched to netplan for configuring the network interfaces. Netplan generates configurations for NetworkManager or systemd-networkd and effectively replaces ifupdown and the /etc/network/interfaces file.
In an install of Ubuntu Desktop, the default netplan configuration comes from /etc/netplan/01-network-manager-all.yaml which reads:
network:
version: 2
renderer: NetworkManager
This basically hands over all network control to NetworkManager. For a static setup we can change the configuration to:
network:
version: 2
renderer: networkd
ethernets:
enp0s25:
dhcp4: no
addresses: [aaa.aaa.aaa.aaa/24]
gateway4: bbb.bbb.bbb.bbb
nameservers:
search: [example.co.uk]
addresses: [xxx.xxx.xxx.xxx,yyy.yyy.yyy.yyy,zzz.zzz.zzz.zzz]
Where enp0s25 is my network interface in this case, the address has a netmask of 255.255.255.0 and the search is the default dns search domain(s) (note this can be vital for getting automounting to work if your setup just uses machine names and assumes the domain is the same).
We have a problem that with recent versions of Ubuntu (16.04 and later) and Debian (8 and later) the normal way we set up automounting to mount our nis users home directories doesn’t work – apparently due to boot ordering issues. (It works fine with Red Hat derivatives). We accidentally found a solution when copying a BSD configuration…
We create a file in /etc/auto.master.d (gets read in by auto.master in the standard Debian/Ubuntu setup):