Troubleshooting Ironic¶
Nova returns “No valid host was found” Error¶
Sometimes Nova Conductor log file “nova-conductor.log” or a message returned from Nova API contains the following error:
NoValidHost: No valid host was found. There are not enough hosts available.
“No valid host was found” means that the Nova Scheduler could not find a bare metal node suitable for booting the new instance.
This in turn usually means some mismatch between resources that Nova expects to find and resources that Ironic advertised to Nova.
A few things should be checked in this case:
Make sure that enough nodes are in
available
state, not in maintenance mode and not already used by an existing instance. Check with the following command:baremetal node list --provision-state available --no-maintenance --unassociated
If this command does not show enough nodes, use generic
baremetal node list
to check other nodes. For example, nodes inmanageable
state should be made available:baremetal node provide <IRONIC NODE>
The Bare metal service automatically puts a node in maintenance mode if there are issues with accessing its management interface. Check the power credentials (e.g.
ipmi_address
,ipmi_username
andipmi_password
) and then move the node out of maintenance mode:baremetal node maintenance unset <IRONIC NODE>
The
node validate
command can be used to verify that all required fields are present. The following command should not return anything:baremetal node validate <IRONIC NODE> | grep -E '(power|management)\W*False'
Maintenance mode will be also set on a node if automated cleaning has failed for it previously.
Make sure that you have Compute services running and enabled:
$ openstack compute service list --service nova-compute +----+--------------+-------------+------+---------+-------+----------------------------+ | ID | Binary | Host | Zone | Status | State | Updated At | +----+--------------+-------------+------+---------+-------+----------------------------+ | 7 | nova-compute | example.com | nova | enabled | up | 2017-09-04T13:14:03.000000 | +----+--------------+-------------+------+---------+-------+----------------------------+
By default, a Compute service is disabled after 10 consecutive build failures on it. This is to ensure that new build requests are not routed to a broken Compute service. If it is the case, make sure to fix the source of the failures, then re-enable it:
openstack compute service set --enable <COMPUTE HOST> nova-compute
Starting with the Pike release, check that all your nodes have the
resource_class
field set using the following command:baremetal node list --fields uuid name resource_class
Then check that the flavor(s) are configured to request these resource classes via their properties:
openstack flavor show <FLAVOR NAME> -f value -c properties
For example, if your node has resource class
baremetal-large
, it will be matched by a flavor with propertyresources:CUSTOM_BAREMETAL_LARGE
set to1
. See Create flavors for use with the Bare Metal service for more details on the correct configuration.Upon scheduling, Nova will query the Placement API service for the available resource providers (in the case of Ironic: nodes with a given resource class). If placement does not have any allocation candidates for the requested resource class, the request will result in a “No valid host was found” error. It is hence sensible to check if Placement is aware of resource providers (nodes) for the requested resource class with:
$ openstack allocation candidate list --resource CUSTOM_BAREMETAL_LARGE='1' +---+-----------------------------+--------------------------------------+-------------------------------+ | # | allocation | resource provider | inventory used/capacity | +---+-----------------------------+--------------------------------------+-------------------------------+ | 1 | CUSTOM_BAREMETAL_LARGE=1 | 2f7b9c69-c1df-4e40-b94e-5821a4ea0453 | CUSTOM_BAREMETAL_LARGE=0/1 | +---+-----------------------------+--------------------------------------+-------------------------------+
For Ironic, the resource provider is the UUID of the available Ironic node. If this command returns an empty list (or does not contain the targeted resource provider), the operator needs to understand first, why the resource tracker has not reported this provider to placement. Potential explanations include:
the resource tracker cycle has not finished yet and the resource provider will appear once it has (the time to finish the cycle scales linearly with the number of nodes the corresponding
nova-compute
service manages);the node is in a state where the resource tracker does not consider it to be eligible for scheduling, e.g. when the node has
maintenance
set toTrue
; make sure the target nodes are inavailable
andmaintenance
isFalse
;
If you do not use scheduling based on resource classes, then the node’s properties must have been set either manually or via inspection. For each node with
available
state check that theproperties
JSON field has valid values for the keyscpus
,cpu_arch
,memory_mb
andlocal_gb
. Example of valid properties:$ baremetal node show <IRONIC NODE> --fields properties +------------+------------------------------------------------------------------------------------+ | Property | Value | +------------+------------------------------------------------------------------------------------+ | properties | {u'memory_mb': u'8192', u'cpu_arch': u'x86_64', u'local_gb': u'41', u'cpus': u'4'} | +------------+------------------------------------------------------------------------------------+
Warning
If you’re using exact match filters in the Nova Scheduler, make sure the flavor and the node properties match exactly.
The Nova flavor that you are using does not match any properties of the available Ironic nodes. Use
openstack flavor show <FLAVOR NAME>
to compare. The extra specs in your flavor starting with
capability:
should match ones innode.properties['capabilities']
.Note
The format of capabilities is different in Nova and Ironic. E.g. in Nova flavor:
$ openstack flavor show <FLAVOR NAME> -c properties +------------+----------------------------------+ | Field | Value | +------------+----------------------------------+ | properties | capabilities:boot_option='local' | +------------+----------------------------------+
But in Ironic node:
$ baremetal node show <IRONIC NODE> --fields properties +------------+-----------------------------------------+ | Property | Value | +------------+-----------------------------------------+ | properties | {u'capabilities': u'boot_option:local'} | +------------+-----------------------------------------+
After making changes to nodes in Ironic, it takes time for those changes to propagate from Ironic to Nova. Check that
openstack hypervisor stats show
correctly shows total amount of resources in your system. You can also check
openstack hypervisor show <IRONIC NODE>
to see the status of individual Ironic nodes as reported to Nova.Figure out which Nova Scheduler filter ruled out your nodes. Check the
nova-scheduler
logs for lines containing something like:Filter ComputeCapabilitiesFilter returned 0 hosts
The name of the filter that removed the last hosts may give some hints on what exactly was not matched. See Nova filters documentation for more details.
If none of the above helped, check Ironic conductor log carefully to see if there are any conductor-related errors which are the root cause for “No valid host was found”. If there are any “Error in deploy of node <IRONIC-NODE-UUID>: [Errno 28] …” error messages in Ironic conductor log, it means the conductor run into a special error during deployment. So you can check the log carefully to fix or work around and then try again.
Patching the Deploy Ramdisk¶
When debugging a problem with deployment and/or inspection you may want to quickly apply a change to the ramdisk to see if it helps. Of course you can inject your code and/or SSH keys during the ramdisk build (depends on how exactly you’ve built your ramdisk). But it’s also possible to quickly modify an already built ramdisk.
Create an empty directory and unpack the ramdisk content there:
$ mkdir unpack
$ cd unpack
$ gzip -dc /path/to/the/ramdisk | cpio -id
The last command will result in the whole Linux file system tree unpacked in the current directory. Now you can modify any files you want. The actual location of the files will depend on the way you’ve built the ramdisk.
Note
On a systemd-based system you can use the systemd-nspawn
tool (from
the systemd-container
package) to create a lightweight container from
the unpacked filesystem tree:
$ sudo systemd-nspawn --directory /path/to/unpacked/ramdisk/ /bin/bash
This will allow you to run commands within the filesystem, e.g. use package manager. If the ramdisk is also systemd-based, and you have login credentials set up, you can even boot a real ramdisk enviroment with
$ sudo systemd-nspawn --directory /path/to/unpacked/ramdisk/ --boot
After you’ve done the modifications, pack the whole content of the current directory back:
$ find . | cpio -H newc -o | gzip -c > /path/to/the/new/ramdisk
Note
You don’t need to modify the kernel (e.g.
tinyipa-master.vmlinuz
), only the ramdisk part.
API Errors¶
The debug_tracebacks_in_api config option may be set to return tracebacks in the API response for all 4xx and 5xx errors.
Retrieving logs from the deploy ramdisk¶
When troubleshooting deployments (specially in case of a deploy failure)
it’s important to have access to the deploy ramdisk logs to be able to
identify the source of the problem. By default, Ironic will retrieve the
logs from the deploy ramdisk when the deployment fails and save it on the
local filesystem at /var/log/ironic/deploy
.
To change this behavior, operators can make the following changes to
/etc/ironic/ironic.conf
under the [agent]
group:
deploy_logs_collect
: Whether Ironic should collect the deployment logs on deployment. Valid values for this option are:on_failure
(default): Retrieve the deployment logs upon a deployment failure.always
: Always retrieve the deployment logs, even if the deployment succeed.never
: Disable retrieving the deployment logs.
deploy_logs_storage_backend
: The name of the storage backend where the logs will be stored. Valid values for this option are:local
(default): Store the logs in the local filesystem.swift
: Store the logs in Swift.
deploy_logs_local_path
: The path to the directory where the logs should be stored, used when thedeploy_logs_storage_backend
is configured tolocal
. By default logs will be stored at /var/log/ironic/deploy.deploy_logs_swift_container
: The name of the Swift container to store the logs, used when the deploy_logs_storage_backend is configured to “swift”. By default ironic_deploy_logs_container.deploy_logs_swift_days_to_expire
: Number of days before a log object is marked as expired in Swift. If None, the logs will be kept forever or until manually deleted. Used when the deploy_logs_storage_backend is configured to “swift”. By default 30 days.
When the logs are collected, Ironic will store a tar.gz file containing
all the logs according to the deploy_logs_storage_backend
configuration option. All log objects will be named with the following
pattern:
<node>[_<instance-uuid>]_<timestamp yyyy-mm-dd-hh:mm:ss>.tar.gz
Note
The instance_uuid field is not required for deploying a node when Ironic is configured to be used in standalone mode. If present it will be appended to the name.
Accessing the log data¶
When storing in the local filesystem¶
When storing the logs in the local filesystem, the log files can
be found at the path configured in the deploy_logs_local_path
configuration option. For example, to find the logs from the node
5e9258c4-cfda-40b6-86e2-e192f523d668
:
$ ls /var/log/ironic/deploy | grep 5e9258c4-cfda-40b6-86e2-e192f523d668
5e9258c4-cfda-40b6-86e2-e192f523d668_88595d8a-6725-4471-8cd5-c0f3106b6898_2016-08-08-13:52:12.tar.gz
5e9258c4-cfda-40b6-86e2-e192f523d668_db87f2c5-7a9a-48c2-9a76-604287257c1b_2016-08-08-14:07:25.tar.gz
Note
When saving the logs to the filesystem, operators may want to enable some form of rotation for the logs to avoid disk space problems.
When storing in Swift¶
When using Swift, operators can associate the objects in the
container with the nodes in Ironic and search for the logs for the node
5e9258c4-cfda-40b6-86e2-e192f523d668
using the prefix parameter.
For example:
$ swift list ironic_deploy_logs_container -p 5e9258c4-cfda-40b6-86e2-e192f523d668
5e9258c4-cfda-40b6-86e2-e192f523d668_88595d8a-6725-4471-8cd5-c0f3106b6898_2016-08-08-13:52:12.tar.gz
5e9258c4-cfda-40b6-86e2-e192f523d668_db87f2c5-7a9a-48c2-9a76-604287257c1b_2016-08-08-14:07:25.tar.gz
To download a specific log from Swift, do:
$ swift download ironic_deploy_logs_container "5e9258c4-cfda-40b6-86e2-e192f523d668_db87f2c5-7a9a-48c2-9a76-604287257c1b_2016-08-08-14:07:25.tar.gz"
5e9258c4-cfda-40b6-86e2-e192f523d668_db87f2c5-7a9a-48c2-9a76-604287257c1b_2016-08-08-14:07:25.tar.gz [auth 0.341s, headers 0.391s, total 0.391s, 0.531 MB/s]
The contents of the log file¶
The log is just a .tar.gz
file that can be extracted as:
$ tar xvf <file path>
The contents of the file may differ slightly depending on the distribution that the deploy ramdisk is using:
For distributions using
systemd
there will be a file called journal which contains all the system logs collected via thejournalctl
command.For other distributions, the ramdisk will collect all the contents of the
/var/log
directory.
For all distributions, the log file will also contain the output of
the following commands (if present): ps
, df
, ip addr
and
iptables
.
Here’s one example when extracting the content of a log file for a
distribution that uses systemd
:
$ tar xvf 5e9258c4-cfda-40b6-86e2-e192f523d668_88595d8a-6725-4471-8cd5-c0f3106b6898_2016-08-08-13:52:12.tar.gz
df
ps
journal
ip_addr
iptables
DHCP during PXE or iPXE is inconsistent or unreliable¶
This can be caused by the spanning tree protocol delay on some switches. The delay prevents the switch port moving to forwarding mode during the nodes attempts to PXE, so the packets never make it to the DHCP server. To resolve this issue you should set the switch port that connects to your baremetal nodes as an edge or PortFast type port. Configured in this way the switch port will move to forwarding mode as soon as the link is established. An example on how to do that for a Cisco Nexus switch is:
$ config terminal
$ (config) interface eth1/11
$ (config-if) spanning-tree port type edge
Why does X issue occur when I am using LACP bonding with iPXE?¶
If you are using iPXE, an unfortunate aspect of its design and interaction with networking is an automatic response as a Link Aggregation Control Protocol (or LACP) peer to remote switches. iPXE does this for only the single port which is used for network booting.
In theory, this may help establish the port link-state faster with some switch vendors, but the official reasoning as far as the Ironic Developers are aware is not documented for iPXE. The end result of this is that once iPXE has stopped responding to LACP messages from the peer port, which occurs as part of the process of booting a ramdisk and iPXE handing over control to a full operating-system, switches typically begin a timer to determine how to handle the failure. This is because, depending on the mode of LACP, this can be interpreted as a switch or network fabric failure.
This may demonstrate as any number of behaviors or issues from ramdisks finding they are unable to acquire DHCP addresses over the network interface to downloads abruptly stalling, to even minor issues such as LLDP port data being unavailable in introspection.
Overall:
Ironic’s agent doesn’t officially support LACP and the Ironic community generally believes this may cause more problems than it would solve. During the Victoria development cycle, we added retry logic for most actions in an attempt to navigate the worst-known default hold-down timers to help ensure a deployment does not fail due to a short-lived transitory network connectivity failure in the form of a switch port having moved to a temporary blocking state. Where applicable and possible, many of these patches have been backported to supported releases, however users of the iSCSI deployment interface will see the least capability for these sorts of situations to be handled automatically. These patches also require that the switchport has an eventual fallback to a non-bonded mode. If the port remains in a blocking state, then traffic will be unable to flow and the deloyment is likely to time out.
If you must use LACP, consider
passive
LACP negotiation settings in the network switch as opposed toactive
. The difference being with passive the connected workload is likely a server where it should likely request the switch to establish the Link Aggregate. This is instead of being treated as if it’s possibly another switch.Consult your switch vendor’s support forums. Some vendors have recommended port settings for booting machines using iPXE with their switches.
IPMI errors¶
When working with IPMI, several settings need to be enabled depending on vendors.
Enable IPMI over LAN¶
Machines may not have IPMI access over LAN enabled by default. This could cause the IPMI port to be unreachable through ipmitool, as shown:
$ ipmitool -I lan -H ipmi_host -U ipmi_user -P ipmi_pass chassis power status
Error: Unable to establish LAN session
To fix this, enable IPMI over lan setting using your BMC tool or web app.
Troubleshooting lanplus interface¶
When working with lanplus interfaces, you may encounter the following error:
$ ipmitool -I lanplus -H ipmi_host -U ipmi_user -P ipmi_pass power status
Error in open session response message : insufficient resources for session
Error: Unable to establish IPMI v2 / RMCP+ session
To fix that issue, please enable RMCP+ Cipher Suite3 Configuration setting using your BMC tool or web app.
Why are my nodes stuck in a “-ing” state?¶
The Ironic conductor uses states ending with ing
as a signifier that
the conductor is actively working on something related to the node.
Often, this means there is an internal lock or reservation
set on the node
and the conductor is downloading, uploading, or attempting to perform some
sort of Input/Output operation.
In the case the conductor gets stuck, these operations should timeout, but there are cases in operating systems where operations are blocked until completion. These sorts of operations can vary based on the specific environment and operating configuration.
What can cause these sorts of failures?¶
Typical causes of such failures are going to be largely rooted in the concept
of iowait
, either in the form of downloading from a remote host or
reading or writing to the disk of the conductor. An operator can use the
iostat tool to
identify the percentage of CPU time spent waiting on storage devices.
The fields that will be particularly important are the iowait
, await
,
and tps
ones, which can be read about in the iostat
manual page.
In the case of network file systems, for backing components such as image
caches or distributed tftpboot
or httpboot
folders, IO operations
failing on these can, depending on operating system and underlying client
settings, cause threads to be stuck in a blocking wait state, which is
realistically undetectable short the operating system logging connectivity
errors or even lock manager access errors.
For example with
nfs,
the underlying client recovery behavior, in terms of soft
, hard
,
softreval
, nosoftreval
, will largely impact this behavior, but also
NFS server settings can impact this behavior. A solid sign that this is a
failure, is when an ls /path/to/nfs
command hangs for a period of time.
In such cases, the Storage Administrator should be consulted and network
connectivity investigated for errors before trying to recover to
proceed.
File Size != Disk Size¶
An easy to make misconception is that a 2.4 GB file means that only 2.4 GB
is written to disk. But if that file’s virtual size is 20 GB, or 100 GB
things can become very problematic and extend the amount of time the node
spends in deploying
and deploy wait
states.
Again, these sorts of cases will depend upon the exact configuration of the deployment, but hopefully these are areas where these actions can occur.
Conversion to raw image files upon download to the conductor, from the
[DEFAULT]force_raw_images
option, in particular with theiscsi
deployment interface. Users using glance and thedirect
deployment interface may also experience issues here as the conductor will cache the image to be written which takes place when the[agent]image_download_source
is set tohttp
instead ofswift
.Write of a QCOW2 file over the
iscsi
deployment interface from the conductor to the node being deployed can result in large amounts of “white space” to be written to be transmitted over the wire and written to the end device.
Note
The QCOW2 image conversion utility does consume quite a bit of memory
when converting images or writing them to the end storage device. This
is because the files are not sequential in nature, and must be re-assembled
from an internal block mapping. Internally Ironic limits this to 1GB
of RAM. Operators performing large numbers of deployments may wish to
explore the direct
deployment interface in these sorts of cases in
order to minimize the conductor becoming a limiting factor due to memory
and network IO.
Why are my nodes stuck in a “wait” state?¶
The Ironic conductor uses states containing wait
as a signifier that
the conductor is waiting for a callback from another component, such as
the Ironic Python Agent or the Inspector. If this feedback does not arrive,
the conductor will time out and the node will eventually move to a failed
state. Depending on the configuration and the circumstances, however, a node
can stay in a wait
state for a long time or even never time out. The list
of such wait states includes:
clean wait
for cleaning,inspect wait
for introspection,rescue wait
for rescueing, andwait call-back
for deploying.
Communication issues between the conductor and the node¶
One of the most common issues when nodes seem to be stuck in a wait state occur when the node never received any instructions or does not react as expected: the conductor moved the node to a wait state but the node will never call back. Examples include wrong ciphers which will make ipmitool get stuck or BMCs in a state where they accept commands, but don’t do the requested task (or only a part of it, like shutting off, but not starting). It is useful in these cases to see via a ping or the console if and which action the node is performing. If the node does not seem to react to the requests sent be the conductor, it may be worthwhile to try the corresponding action out-of-band, e.g. confirm that power on/off commands work when directly sent to the BMC. The section on IPMI errors. above gives some additional points to check. In some situations, a BMC reset may be necessary.
Ironic Python Agent stuck¶
Nodes can also get remain in a wait state when the component the conductor is waiting for gets stuck, e.g. when a hardware manager enters a loop or is waiting for an event that is never happening. In these cases, it might be helpful to connect to the IPA and inspect its logs, see the trouble shooting guide of the ironic-python-agent (IPA) on how to do this.
Deployments fail with “failed to update MAC address”¶
The design of the integration with the Networking service (neutron) is such that once virtual ports have been created in the API, their MAC address must be updated in order for the DHCP server to be able to appropriately reply.
This can sometimes result in errors being raised indicating that the MAC address is already in use. This is because at some point in the past, a virtual interface was orphaned either by accident or by some unexpected glitch, and a previous entry is still present in Neutron.
This error looks something like this when reported in the ironic-conductor log output.:
Failed to update MAC address on Neutron port 305beda7-0dd0-4fec-b4d2-78b7aa4e8e6a.: MacAddressInUseClient: Unable to complete operation for network 1e252627-6223-4076-a2b9-6f56493c9bac. The mac address 52:54:00:7c:c4:56 is in use.
Because we have no idea about this entry, we fail the deployment process as we can’t make a number of assumptions in order to attempt to automatically resolve the conflict.
How did I get here?¶
Originally this was a fairly easy issue to encounter. The retry logic path which resulted between the Orchestration (heat) and Compute (nova) services, could sometimes result in additional un-necessary ports being created.
Bugs of this class have been largely resolved since the Rocky development cycle. Since then, the way this can become encountered is due to Networking (neutron) VIF attachments not being removed or deleted prior to deleting a port in the Bare Metal service.
Ultimately, the key of this is that the port is being deleted. Under most operating circumstances, there really is no need to delete the port, and VIF attachments are stored on the port object, so deleting the port CAN result in the VIF not being cleaned up from Neutron.
Under normal circumstances, when deleting ports, a node should be in a
stable state, and the node should not be provisioned. If the
baremetal port delete
command fails, this may indicate that
a known VIF is still attached. Generally if they are transitory from cleaning,
provisioning, rescuing, or even inspection, getting the node to the
available
state wil unblock your delete operation, that is unless there is
a tenant VIF attahment. In that case, the vif will need to be removed from
with-in the Bare Metal service using the
baremetal node vif detach
command.
A port can also be checked to see if there is a VIF attachment by consulting
the port’s internal_info
field.
Warning
The maintenance
flag can be used to force the node’s port to be
deleted, however this will disable any check that would normally block
the user from issuing a delete and accidently orphaning the VIF attachment
record.
How do I resolve this?¶
Generally, you need to identify the port with the offending MAC address. Example:
openstack port list –mac-address 52:54:00:7c:c4:56
From the command’s output, you should be able to identify the id
field.
Using that, you can delete the port. Example:
openstack port delete <id>
Warning
Before deleting a port, you should always verify that it is no longer in use or no longer seems applicable/operable. If multiple deployments of the Bare Metal service with a single Neutron, the possibility that a inventory typo, or possibly even a duplicate MAC address exists, which could also produce the same basic error message.
My test VM image does not deploy – mount point does not exist¶
What is likely occuring¶
The image attempting to be deployed likely is a partition image where
the file system that the user wishes to boot from lacks the required
folders, such as /dev
and /proc
, which are required to install
a bootloader for a Linux OS image
It should be noted that similar errors can also occur with whole disk images where we are attempting to setup the UEFI bootloader configuration. That being said, in this case, the image is likely invalid or contains an unexpected internal structure.
Users performing testing may choose something that they believe
will work based on it working for virtual machines. These images are often
attractive for testing as they are generic and include basic support
for establishing networking and possibly installing user keys.
Unfortunately, these images often lack drivers and firmware required for
many different types of physical hardware which makes using them
very problematic. Additionally, images such as Cirros
do not have any contents in the root filesystem (i.e. an empty filesystem),
as they are designed for the ramdisk
to write the contents to disk upon
boot.
How do I not encounter this issue?¶
We generally recommend using diskimage-builder or vendor supplied images. Centos, Ubuntu, Fedora, and Debian all publish operating system images which do generally include drivers and firmware for physical hardware. Many of these published “cloud” images, also support auto-configuration of networking AND population of user keys.
Issues with autoconfigured TLS¶
These issues will manifest as an error in ironic-conductor
logs looking
similar to (lines are wrapped for readability):
ERROR ironic.drivers.modules.agent_client [-]
Failed to connect to the agent running on node d7c322f0-0354-4008-92b4-f49fb2201001
for invoking command clean.get_clean_steps. Error:
HTTPSConnectionPool(host='192.168.123.126', port=9999): Max retries exceeded with url:
/v1/commands/?wait=true&agent_token=<token> (Caused by
SSLError(SSLError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:897)'),)):
requests.exceptions.SSLError: HTTPSConnectionPool(host='192.168.123.126', port=9999):
Max retries exceeded with url: /v1/commands/?wait=true&agent_token=<token>
(Caused by SSLError(SSLError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:897)'),))
The cause of the issue is that the Bare Metal service cannot access the ramdisk
with the TLS certificate provided by the ramdisk on first heartbeat. You can
inspect the stored certificate in /var/lib/ironic/certificates/<node>.crt
.
You can try connecting to the ramdisk using the IP address in the log message:
curl -vL https://<IP address>:9999/v1/commands \
--cacert /var/lib/ironic/certificates/<node UUID>.crt
You can get the detailed information about the certificate using openSSL:
openssl x509 -text -noout -in /var/lib/ironic/certificates/<node UUID>.crt
Clock skew¶
One possible source of the problem is a discrepancy between the hardware
clock on the node and the time on the machine with the Bare Metal service.
It can be detected by comparing the Not Before
field in the openssl
output with the timestamp of a log message.
The recommended solution is to enable the NTP support in ironic-python-agent by
passing the ipa-ntp-server
argument with an address of an NTP server
reachable by the node.
If it is not possible, you need to ensure the correct hardware time on the machine. Keep in mind a potential issue with timezones: an ability to store timezone in hardware is pretty recent and may not be available. Since ironic-python-agent is likely operating in UTC, the hardware clock should also be set in UTC.
Note
Microsoft Windows uses local time by default, so a machine that has previously run Windows will likely have wrong time.
I changed ironic.conf, and now I can’t edit my nodes.¶
Whenever a node is created in ironic, default interfaces are identified
as part of driver composition. This maybe sourced from explicit default
values which have been set in ironic.conf
or by the interface order
for the enabled interfaces list. The result of this is that the
ironic-conductor
cannot spawn a task
using the composed driver,
as a portion of the driver is no longer enabled. This makes it difficult
to edit or update the node if the settings have been changed.
For example, with networking interfaces, if you have
default_network_interface=neutron
or
enabled_network_interfaces=neutron,flat
in your ironic.conf
, nodes would have been created with the neutron
network interface.
This is because default_network_interface
overrides the setting
for new nodes, and that setting is saved to the database nodes table.
Similarly, the order of enabled_network_interfaces
takes priority, and
the first entry in the list is generally set to the default for the node upon
creation, and that record is saved to the database nodes table.
The only case where driver composition does not calculate a default is if an explicit value is provided upon the creation of the node.
Example failure¶
A node in this state, when the network_interface
was saved as neutron
,
yet the neutron
interface is no longer enabled will fail basic state
transition requests.:
$ baremetal node manage 7164efca-37ab-1213-1112-b731cf795a5a Could not find the following interface in the ‘ironic.hardware.interfaces.network’ entrypoint: neutron. Valid interfaces are [‘flat’]. (HTTP 400)
How to fix this?¶
Revert the changes you made to ironic.conf
.
This applies to any changes to any default_*_interface
options or the
order of interfaces in the for the enabled_*_interfaces
options.
Once the conductor has been restarted with the updated configuration, you
should now be able to update the interface using the baremetal node set
command. In this example we use the network_interface
as this is most
commonly where it is encountered.:
$ baremetal node set $NAME_OR_UUID –network-interface flat
Note
There are additional paths one can take to remedy this sort of issue, however we encourage operators to be mindful of operational consistency when making major configuration changes.
Once you have updated the saved interfaces, you should be able to safely
return the ironic.conf
configuration change in changing what interfaces
are enabled by the conductor.
I’m getting Out of Memory errors¶
This issue, also known as the “the OOMKiller got my conductor” case, is where your OS system memory reaches a point where the operating system engages measures to shed active memory consumption in order to prevent a complete failure of the machine. Unfortunately this can cause unpredictable behavior.
How did I get here?¶
One of the major consumers of memory in a host running an ironic-conductor is
transformation of disk images using the qemu-img
tool. This tool, because
the disk images it works with are both compressed and out of linear block
order, requires a considerable amount of memory to efficently re-assemble
and write-out a disk to a device, or to simply convert the format such as
to a raw
image.
By default, ironic’s configuration limits this conversion to 1 GB of RAM for the process, but each conversion does cause additional buffer memory to be used, which increases overall system memory pressure. Generally memory pressure alone from buffers will not cause an out of memory condition, but the multiple conversions or deployments running at the same time CAN cause extreme memory pressure and risk the system running out of memory.
How do I resolve this?¶
This can be addressed a few different ways:
Use raw images, however these images can be substantially larger and require more data to be transmitted “over the wire”.
Add more physical memory.
Add swap space.
Reduce concurrency, possibly via another conductor or changing the nova-compute.conf
max_concurrent_builds
parameter.Or finally, adjust the
[DEFAULT]minimum_required_memory
parameter in your ironic.conf file. The default should be considered a “default of last resort” and you may need to reserve additional memory. You may also wish to adjust the[DEFAULT]minimum_memory_wait_retries
and[DEFAULT]minimum_memory_wait_time
parameters.