Commit 483aa6294b introduced a regression, causing
spurious warnings to be shown when starting a daemon for the first time after
a fresh install:
docker info
...
WARNING: IPv4 forwarding is disabled
WARNING: bridge-nf-call-iptables is disabled
WARNING: bridge-nf-call-ip6tables is disabled
The information shown is incorrect, as checking the corresponding options on
the system, shows that these options are available:
cat /proc/sys/net/ipv4/ip_forward
1
cat /proc/sys/net/bridge/bridge-nf-call-iptables
1
cat /proc/sys/net/bridge/bridge-nf-call-ip6tables
1
The reason this is failing is because the daemon itself reconfigures those
options during networking initialization in `configureIPForwarding()`;
cf4595265e/libnetwork/drivers/bridge/setup_ip_forwarding.go (L14-L25)
Network initialization happens in the `daemon.restore()` function within `daemon.NewDaemon()`:
cf4595265e/daemon/daemon.go (L475-L478)
However, 483aa6294b moved detection of features
earlier in the `daemon.NewDaemon()` function, and collects the system information
(`d.RawSysInfo()`) before we enter `daemon.restore()`;
cf4595265e/daemon/daemon.go (L1008-L1011)
For optimization (collecting the system information comes at a cost), those
results are cached on the daemon, and will only be performed once (using a
`sync.Once`).
This patch:
- introduces a `getSysInfo()` utility, which collects system information without
caching the results
- uses `getSysInfo()` to collect the preliminary information needed at that
point in the daemon's lifecycle.
- moves printing warnings to the end of `daemon.NewDaemon()`, after all information
can be read correctly.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The `daemon.RawSysInfo()` function can be a heavy operation, as it collects
information about all cgroups on the host, networking, AppArmor, Seccomp, etc.
While looking at our code, I noticed that various parts in the code call this
function, potentially even _multiple times_ per container, for example, it is
called from:
- `verifyPlatformContainerSettings()`
- `oci.WithCgroups()` if the daemon has `cpu-rt-period` or `cpu-rt-runtime` configured
- in `ContainerDecoder.DecodeConfig()`, which is called on boith `container create` and `container commit`
Given that this information is not expected to change during the daemon's
lifecycle, and various information coming from this (such as seccomp and
apparmor status) was already cached, we may as well load it once, and cache
the results in the daemon instance.
This patch updates `daemon.RawSysInfo()` to use a `sync.Once()` so that
it's only executed once for the daemon's lifecycle.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
The "quiet" argument was only used in a single place (at daemon startup), and
every other use had to pass "false" to prevent this function from logging
warnings.
Now that SysInfo contains the warnings that occurred when collecting the
system information, we can make leave it up to the caller to use those
warnings (and log them if wanted).
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Handle the case of systemd-resolved, and if in place
use a different resolv.conf source.
Set appropriately the option on libnetwork.
Move unix specific code to container_operation_unix
Signed-off-by: Flavio Crisciani <flavio.crisciani@docker.com>