libnetwork/etchosts: add host.containers.internal for machine #2464
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Reviewer's GuideAdds a one-time DNS lookup for host.containers.internal and plugs that lookup into GetHostContainersInternalIP so custom --add-host entries resolve correctly when running in a Podman machine with gvproxy. Sequence diagram for resolving host.containers.internal in Podman machinesequenceDiagram
participant User
participant Podman
participant etchosts
participant machine
participant net
User->>Podman: Run container with --add-host foobar:host-gateway
Podman->>etchosts: Call GetHostContainersInternalIP(opts)
etchosts->>machine: IsGvProxyBased()
alt machine is gvproxy-based
etchosts->>etchosts: machineHostContainersInternalIP()
etchosts->>net: LookupIP("host.containers.internal")
net-->>etchosts: IP address
etchosts-->>Podman: Return resolved IP
else not gvproxy-based
etchosts-->>Podman: Use default logic
end
Podman-->>User: /etc/hosts updated with correct IP
Class diagram for updated GetHostContainersInternalIP logicclassDiagram
class HostContainersInternalOptions {
Conf ConfType
PreferIP string
}
class ConfType {
Containers ContainersType
}
class ContainersType {
HostContainersInternalIP string
}
class machine {
+IsGvProxyBased() bool
}
class etchosts {
+GetHostContainersInternalIP(opts HostContainersInternalOptions) string
+machineHostContainersInternalIP() string
}
HostContainersInternalOptions --> ConfType : Conf
ConfType --> ContainersType : Containers
etchosts ..> machine : uses
etchosts ..> HostContainersInternalOptions : uses
etchosts ..> machineHostContainersInternalIP : calls
machineHostContainersInternalIP ..> net : LookupIP
File-Level Changes
Tips and commandsInteracting with Sourcery
Customizing Your ExperienceAccess your dashboard to:
Getting Help
|
![sourcery-ai[bot]](https://avatars.githubusercontent.com/in/48477?s=60&v=4){kind=small}
Contributor
|
[APPROVALNOTIFIER] This PR is APPROVED This pull-request has been approved by: Luap99, sourcery-ai[bot] The full list of commands accepted by this bot can be found here. The pull request process is described here DetailsNeeds approval from an approver in each of these files:
Approvers can indicate their approval by writing |
Member
|
LGTM, i assume there is no value in logging any errors there in the new function. |
Member
Author
I also could log it as warning so we see it in the journal if we ever have to ask users for logs it might be worth it. gvproxy should always resolve the name and we have the condition that checks that we are a gvproxy machine so I guess this never fails unless gvproxy is misbehaving. I think I need to update the docs here as well as we leaked some implementation details into them that now need to be updated. |
When running inside podman machine we cannot use the normal ip lookup logic for host.containers.internal because that should refer to the actual host system and not the VM ip. gvproxy already resolves the host.containers.internal name correctly but the issue is when a users wants to set a custom name via --add-host foobar:host-gateway then we need to know the actual ip to replace the host-gateway part. Right now we just always error which is not good. To fix this just look up the name ourselves so we can add it to /etc/hosts. Fixes: containers/podman#21681 Signed-off-by: Paul Holzinger <[email protected]>
Member
|
LGTM |
Member
Author
|
@mheon PTAL (For reference I tested this change inside the machine and it worked as expected) |
Member
|
/lgtm |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
When running inside podman machine we cannot use the normal ip lookup logic for host.containers.internal because that should refer to the actual host system and not the VM ip.
gvproxy already resolves the host.containers.internal name correctly but the issue is when a users wants to set a custom name via --add-host foobar:host-gateway then we need to know the actual ip to replace the host-gateway part. Right now we just always error which is not good.
To fix this just look up the name ourselves so we can add it to /etc/hosts.
Fixes: containers/podman#21681
Summary by Sourcery
Resolve and cache the host.containers.internal address via DNS in Podman machine mode so that custom host-gateway mappings can be added to /etc/hosts without errors
New Features:
Bug Fixes:
Enhancements: