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Discrepancy: systemd unit for k0scontroller sets Restart=always (causes controller restart on apt operations)
Before creating an issue, make sure you've checked the following:
- [x] You are running the latest released version of k0s
- [x] Make sure you've searched for existing issues, both open and closed
- [x] Make sure you've searched for PRs too, a fix might've been merged already
- [x] You're looking at docs for the released version, "main" branch docs are usually ahead of released versions.
Platform
Linux 6.8.0-87-generic #88-Ubuntu SMP PREEMPT_DYNAMIC Sat Oct 11 09:28:41 UTC 2025 x86_64 GNU/Linux
PRETTY_NAME="Ubuntu 24.04.2 LTS"
NAME="Ubuntu"
Version
v1.33.3+k0s.0
Sysinfo
~# k0s sysinfo
Total memory: 11.7 GiB (pass)
File system of /var/lib/k0s: ext4 (pass)
Disk space available for /var/lib/k0s: 20.9 GiB (pass)
Relative disk space available for /var/lib/k0s: 44% (pass)
Name resolution: localhost: [::1 127.0.0.1] (pass)
Operating system: Linux (pass)
Linux kernel release: 6.8.0-87-generic (pass)
Max. file descriptors per process: current: 1048575 / max: 1048576 (pass)
AppArmor: active (pass)
Executable in PATH: modprobe: /usr/sbin/modprobe (pass)
Executable in PATH: mount: /usr/bin/mount (pass)
Executable in PATH: umount: /usr/bin/umount (pass)
/proc file system: mounted (0x9fa0) (pass)
Control Groups: version 2 (pass)
cgroup controller "cpu": available (is a listed root controller) (pass)
cgroup controller "cpuacct": available (via cpu in version 2) (pass)
cgroup controller "cpuset": available (is a listed root controller) (pass)
cgroup controller "memory": available (is a listed root controller) (pass)
cgroup controller "devices": available (device filters attachable) (pass)
cgroup controller "freezer": available (cgroup.freeze exists) (pass)
cgroup controller "pids": available (is a listed root controller) (pass)
cgroup controller "hugetlb": available (is a listed root controller) (pass)
cgroup controller "blkio": available (via io in version 2) (pass)
CONFIG_CGROUPS: Control Group support: built-in (pass)
CONFIG_CGROUP_SCHED: Group CPU scheduler: built-in (pass)
CONFIG_FAIR_GROUP_SCHED: Group scheduling for SCHED_OTHER: built-in (pass)
CONFIG_CFS_BANDWIDTH: CPU bandwidth provisioning for FAIR_GROUP_SCHED: built-in (pass)
CONFIG_BLK_CGROUP: Block IO controller: built-in (pass)
CONFIG_NAMESPACES: Namespaces support: built-in (pass)
CONFIG_UTS_NS: UTS namespace: built-in (pass)
CONFIG_IPC_NS: IPC namespace: built-in (pass)
CONFIG_PID_NS: PID namespace: built-in (pass)
CONFIG_NET_NS: Network namespace: built-in (pass)
CONFIG_NET: Networking support: built-in (pass)
CONFIG_INET: TCP/IP networking: built-in (pass)
CONFIG_IPV6: The IPv6 protocol: built-in (pass)
CONFIG_NETFILTER: Network packet filtering framework (Netfilter): built-in (pass)
CONFIG_NETFILTER_ADVANCED: Advanced netfilter configuration: built-in (pass)
CONFIG_NF_CONNTRACK: Netfilter connection tracking support: module (pass)
CONFIG_NETFILTER_XTABLES: Netfilter Xtables support: module (pass)
CONFIG_NETFILTER_XT_TARGET_REDIRECT: REDIRECT target support: module (pass)
CONFIG_NETFILTER_XT_MATCH_COMMENT: "comment" match support: module (pass)
CONFIG_NETFILTER_XT_MARK: nfmark target and match support: module (pass)
CONFIG_NETFILTER_XT_SET: set target and match support: module (pass)
CONFIG_NETFILTER_XT_TARGET_MASQUERADE: MASQUERADE target support: module (pass)
CONFIG_NETFILTER_XT_NAT: "SNAT and DNAT" targets support: module (pass)
CONFIG_NETFILTER_XT_MATCH_ADDRTYPE: "addrtype" address type match support: module (pass)
CONFIG_NETFILTER_XT_MATCH_CONNTRACK: "conntrack" connection tracking match support: module (pass)
CONFIG_NETFILTER_XT_MATCH_MULTIPORT: "multiport" Multiple port match support: module (pass)
CONFIG_NETFILTER_XT_MATCH_RECENT: "recent" match support: module (pass)
CONFIG_NETFILTER_XT_MATCH_STATISTIC: "statistic" match support: module (pass)
CONFIG_NETFILTER_NETLINK: module (pass)
CONFIG_NF_NAT: module (pass)
CONFIG_IP_SET: IP set support: module (pass)
CONFIG_IP_SET_HASH_IP: hash:ip set support: module (pass)
CONFIG_IP_SET_HASH_NET: hash:net set support: module (pass)
CONFIG_IP_VS: IP virtual server support: module (pass)
CONFIG_IP_VS_NFCT: Netfilter connection tracking: built-in (pass)
CONFIG_IP_VS_SH: Source hashing scheduling: module (pass)
CONFIG_IP_VS_RR: Round-robin scheduling: module (pass)
CONFIG_IP_VS_WRR: Weighted round-robin scheduling: module (pass)
CONFIG_NF_CONNTRACK_IPV4: IPv4 connection tracking support (required for NAT): unknown (warning)
CONFIG_NF_REJECT_IPV4: IPv4 packet rejection: module (pass)
CONFIG_NF_NAT_IPV4: IPv4 NAT: unknown (warning)
CONFIG_IP_NF_IPTABLES: IP tables support: module (pass)
CONFIG_IP_NF_FILTER: Packet filtering: module (pass)
CONFIG_IP_NF_TARGET_REJECT: REJECT target support: module (pass)
CONFIG_IP_NF_NAT: iptables NAT support: module (pass)
CONFIG_IP_NF_MANGLE: Packet mangling: module (pass)
CONFIG_NF_DEFRAG_IPV4: module (pass)
CONFIG_NF_CONNTRACK_IPV6: IPv6 connection tracking support (required for NAT): unknown (warning)
CONFIG_NF_NAT_IPV6: IPv6 NAT: unknown (warning)
CONFIG_IP6_NF_IPTABLES: IP6 tables support: module (pass)
CONFIG_IP6_NF_FILTER: Packet filtering: module (pass)
CONFIG_IP6_NF_MANGLE: Packet mangling: module (pass)
CONFIG_IP6_NF_NAT: ip6tables NAT support: module (pass)
CONFIG_NF_DEFRAG_IPV6: module (pass)
CONFIG_BRIDGE: 802.1d Ethernet Bridging: module (pass)
CONFIG_LLC: module (pass)
CONFIG_STP: module (pass)
CONFIG_EXT4_FS: The Extended 4 (ext4) filesystem: built-in (pass)
CONFIG_PROC_FS: /proc file system support: built-in (pass)
What happened?
Systemd unit for k0scontroller sets Restart=always, causing restarts whenever systemd reloads or restarts services -- including during apt install/upgrade operations. This is unexpected and not documented in the repo template.
Steps to reproduce
- Install k0s with systemd as init system
- Check /etc/systemd/system/k0scontroller.service on host
- Check pkg/install/systemd_linux.go in the k0s source repository
- Observe Restart=always is present on host but absent in source template
- Run 'apt install something' and see k0scontroller is restarted
Expected behavior
Restart behavior should be consistent and documented. Project should clarify intended Restart= policy (always/on-failure/none/etc) and document side effects on maintenance operations. Prefer avoiding unnecessary restarts on unrelated package upgrades.
Actual behavior
Inconsistent template and installed file; unexpected restarts during apt/dpkg operations cause cluster downtime.
Screenshots and logs
~# apt install zip
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following additional packages will be installed:
unzip
The following NEW packages will be installed:
unzip zip
0 upgraded, 2 newly installed, 0 to remove and 0 not upgraded.
Need to get 350 kB of archives.
After this operation, 933 kB of additional disk space will be used.
Do you want to continue? [Y/n] y
Get:1 http://de.archive.ubuntu.com/ubuntu noble-updates/main amd64 unzip amd64 6.0-28ubuntu4.1 [174 kB]
Get:2 http://de.archive.ubuntu.com/ubuntu noble-updates/main amd64 zip amd64 3.0-13ubuntu0.2 [176 kB]
Fetched 350 kB in 6s (55.8 kB/s)
debconf: delaying package configuration, since apt-utils is not installed
Selecting previously unselected package unzip.
(Reading database ... 115368 files and directories currently installed.)
Preparing to unpack .../unzip_6.0-28ubuntu4.1_amd64.deb ...
Unpacking unzip (6.0-28ubuntu4.1) ...
Selecting previously unselected package zip.
Preparing to unpack .../zip_3.0-13ubuntu0.2_amd64.deb ...
Unpacking zip (3.0-13ubuntu0.2) ...
Setting up unzip (6.0-28ubuntu4.1) ...
Setting up zip (3.0-13ubuntu0.2) ...
Scanning processes...
Scanning candidates...
Scanning linux images...
Running kernel seems to be up-to-date.
Restarting services...
systemctl restart k0scontroller.service
----
# /etc/systemd/system/k0scontroller.service
[Unit]
Description=k0s - Zero Friction Kubernetes
Documentation=https://docs.k0sproject.io
ConditionFileIsExecutable=/usr/local/bin/k0s
After=network-online.target
Wants=network-online.target
[Service]
StartLimitInterval=5
StartLimitBurst=10
ExecStart=/usr/local/bin/k0s controller --config=/etc/k0s/k0s.yaml --data-dir=/var/lib/k0s --enable-worker=true --no-taints=true
RestartSec=10
Delegate=yes
KillMode=process
LimitCORE=infinity
TasksMax=infinity
TimeoutStartSec=0
LimitNOFILE=999999
Restart=always
[Install]
WantedBy=multi-user.target
Additional context
This issue makes host maintenance more difficult, and may surprise operators. Please clarify if Restart=always is required or should be overridable/absent. Applies also to any differences for k0sworker systemd units.
