1podman-container-checkpoint(1G)eneral Commands Manupaoldman-container-checkpoint(1)
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6 podman-container-checkpoint - Checkpoint one or more running containers
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10 podman container checkpoint [options] container [container ...]
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14 podman container checkpoint checkpoints all the processes in one or
15 more containers. A container can be restored from a checkpoint with
16 podman-container-restore. The container IDs or names are used as input.
17 IMPORTANT: If the container is using systemd as entrypoint checkpoint‐
20 ing the container might not be possible.
21
24 --all, -a
25 Checkpoint all running containers.
26 The default is false.
27 IMPORTANT: This OPTION does not need a container name or ID as input
28 argument.
29 --compress, -c=zstd | none | gzip
32 Specify the compression algorithm used for the checkpoint archive cre‐
33 ated with the --export, -e OPTION. Possible algorithms are zstd, none
34 and gzip.
35 One possible reason to use none is to enable faster creation of check‐
36 point archives. Not compressing the checkpoint archive can result in
37 faster checkpoint archive creation.
38 The default is zstd.
39 --create-image=image
42 Create a checkpoint image from a running container. This is a standard
43 OCI image created in the local image store. It consists of a single
44 layer that contains all of the checkpoint files. The content of this
45 image layer is in the same format as a checkpoint created with --ex‐
46 port. A checkpoint image can be pushed to a standard container registry
47 and pulled on a different system to enable container migration. In ad‐
48 dition, the image can be exported with podman image save and inspected
49 with podman inspect. Inspecting a checkpoint image displays additional
50 information, stored as annotations, about the host environment used to
51 do the checkpoint:
52 • io.podman.annotations.checkpoint.name: Human-readable name of
55 the original container.
56 • io.podman.annotations.checkpoint.rawImageName: Unprocessed
58 name of the image used to create the original container (as
59 specified by the user).
60 • io.podman.annotations.checkpoint.rootfsImageID: ID of the im‐
62 age used to create the original container.
63 • io.podman.annotations.checkpoint.rootfsImageName: Image name
65 used to create the original container.
66 • io.podman.annotations.checkpoint.podman.version: Version of
68 Podman used to create the checkpoint.
69 • io.podman.annotations.checkpoint.criu.version: Version of CRIU
71 used to create the checkpoint.
72 • io.podman.annotations.checkpoint.runtime.name: Container run‐
74 time (e.g., runc, crun) used to create the checkpoint.
75 • io.podman.annotations.checkpoint.runtime.version: Version of
77 the container runtime used to create the checkpoint.
78 • io.podman.annotations.checkpoint.conmon.version: Version of
80 conmon used with the original container.
81 • io.podman.annotations.checkpoint.host.arch: CPU architecture
83 of the host on which the checkpoint was created.
84 • io.podman.annotations.checkpoint.host.kernel: Version of Linux
86 kernel of the host where the checkpoint was created.
87 • io.podman.annotations.checkpoint.cgroups.version: cgroup ver‐
89 sion used by the host where the checkpoint was created.
90 • io.podman.annotations.checkpoint.distribution.version: Version
92 of host distribution on which the checkpoint was created.
93 • io.podman.annotations.checkpoint.distribution.name: Name of
95 host distribution on which the checkpoint was created.
96 --export, -e=archive
100 Export the checkpoint to a tar.gz file. The exported checkpoint can be
101 used to import the container on another system and thus enabling con‐
102 tainer live migration. This checkpoint archive also includes all
103 changes to the container's root file-system, if not explicitly disabled
104 using --ignore-rootfs.
105 --file-locks
108 Checkpoint a container with file locks. If an application running in
109 the container is using file locks, this OPTION is required during
110 checkpoint and restore. Otherwise checkpointing containers with file
111 locks is expected to fail. If file locks are not used, this option is
112 ignored.
113 The default is false.
114 --ignore-rootfs
117 If a checkpoint is exported to a tar.gz file it is possible with the
118 help of --ignore-rootfs to explicitly disable including changes to the
119 root file-system into the checkpoint archive file.
120 The default is false.
121 IMPORTANT: This OPTION only works in combination with --export, -e.
122 --ignore-volumes
125 This OPTION must be used in combination with the --export, -e OPTION.
126 When this OPTION is specified, the content of volumes associated with
127 the container is not included into the checkpoint tar.gz file.
128 The default is false.
129 --keep, -k
132 Keep all temporary log and statistics files created by CRIU during
133 checkpointing. These files are not deleted if checkpointing fails for
134 further debugging. If checkpointing succeeds these files are theoreti‐
135 cally not needed, but if these files are needed Podman can keep the
136 files for further analysis.
137 The default is false.
138 --latest, -l
141 Instead of providing the container ID or name, use the last created
142 container. The default is false. IMPORTANT: This OPTION is not avail‐
143 able with the remote Podman client, including Mac and Windows (exclud‐
144 ing WSL2) machines. This OPTION does not need a container name or ID as
145 input argument.
146 --leave-running, -R
149 Leave the container running after checkpointing instead of stopping it.
150 The default is false.
151 --pre-checkpoint, -P
154 Dump the container's memory information only, leaving the container
155 running. Later operations supersedes prior dumps. It only works on runc
156 1.0-rc3 or higher.
157 The default is false.
158 The functionality to only checkpoint the memory of the container and in
161 a second checkpoint only write out the memory pages which have changed
162 since the first checkpoint relies on the Linux kernel's soft-dirty bit,
163 which is not available on all systems as it depends on the system ar‐
164 chitecture and the configuration of the Linux kernel. Podman verifies
165 if the current system supports this functionality and return an error
166 if the current system does not support it.
167 --print-stats
170 Print out statistics about checkpointing the container(s). The output
171 is rendered in a JSON array and contains information about how much
172 time different checkpoint operations required. Many of the checkpoint
173 statistics are created by CRIU and just passed through to Podman. The
174 following information is provided in the JSON array:
175 • podman_checkpoint_duration: Overall time (in microseconds)
178 needed to create all checkpoints.
179 • runtime_checkpoint_duration: Time (in microseconds) the con‐
181 tainer runtime needed to create the checkpoint.
182 • freezing_time: Time (in microseconds) CRIU needed to pause
184 (freeze) all processes in the container (measured by CRIU).
185 • frozen_time: Time (in microseconds) all processes in the con‐
187 tainer were paused (measured by CRIU).
188 • memdump_time: Time (in microseconds) needed to extract all re‐
190 quired memory pages from all container processes (measured by
191 CRIU).
192 • memwrite_time: Time (in microseconds) needed to write all re‐
194 quired memory pages to the corresponding checkpoint image
195 files (measured by CRIU).
196 • pages_scanned: Number of memory pages scanned to determine if
198 they need to be checkpointed (measured by CRIU).
199 • pages_written: Number of memory pages actually written to the
201 checkpoint image files (measured by CRIU).
202 The default is false.
206 --tcp-established
209 Checkpoint a container with established TCP connections. If the check‐
210 point image contains established TCP connections, this OPTION is re‐
211 quired during restore. Defaults to not checkpointing containers with
212 established TCP connections.
213 The default is false.
214 --with-previous
217 Check out the container with previous criu image files in pre-dump. It
218 only works on runc 1.0-rc3 or higher.
219 The default is false.
220 IMPORTANT: This OPTION is not available with --pre-checkpoint.
221 This option requires that the option --pre-checkpoint has been used be‐
224 fore on the same container. Without an existing pre-checkpoint, this
225 option fails.
226 Also see --pre-checkpoint for additional information about --pre-check‐
229 point availability on different systems.
230
233 Make a checkpoint for the container "mywebserver".
234 # podman container checkpoint mywebserver
237 Create a checkpoint image for the container "mywebserver".
241 # podman container checkpoint --create-image mywebserver-checkpoint-1 mywebserver
244 Dumps the container's memory information of the latest container into
248 an archive.
249 # podman container checkpoint -P -e pre-checkpoint.tar.gz -l
252 Keep the container's memory information from an older dump and add the
256 new container's memory information.
257 # podman container checkpoint --with-previous -e checkpoint.tar.gz -l
260 Dump the container's memory information of the latest container into an
264 archive with the specified compress method.
265 # podman container checkpoint -l --compress=none --export=dump.tar
268 # podman container checkpoint -l --compress=gzip --export=dump.tar.gz
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273 podman(1), podman-container-restore(1), criu(8)
274
277 September 2018, Originally compiled by Adrian Reber areber@redhat.com
278 ⟨mailto:areber@redhat.com⟩
279 podman-container-checkpoint(1)