Download etcd 3.7.3

Please check out [CHANGELOG](https://github.com/etcd-io/etcd/blob/main/CHANGELOG/CHANGELOG-3.7.md) for a full list of changes. And make sure to read [upgrade guide](https://etcd.io/docs/v3.7/upgrades/upgrade_3_7/) before upgrading etcd (there may be breaking changes).

For installation guides, please check out [play.etcd.io](http://play.etcd.io) and [operating etcd](https://etcd.io/docs/v3.7/op-guide/). Latest support status for common architectures and operating systems can be found at [supported platforms](https://etcd.io/docs/v3.7/op-guide/supported-platform/).

###### Linux

```sh
ETCD_VER=v3.7.3

# choose either URL
GOOGLE_URL=https://storage.googleapis.com/etcd
GITHUB_URL=https://github.com/etcd-io/etcd/releases/download
DOWNLOAD_URL=${GOOGLE_URL}

rm -f /tmp/etcd-${ETCD_VER}-linux-amd64.tar.gz
rm -rf /tmp/etcd-download-test && mkdir -p /tmp/etcd-download-test

curl -L ${DOWNLOAD_URL}/${ETCD_VER}/etcd-${ETCD_VER}-linux-amd64.tar.gz -o /tmp/etcd-${ETCD_VER}-linux-amd64.tar.gz
tar xzvf /tmp/etcd-${ETCD_VER}-linux-amd64.tar.gz -C /tmp/etcd-download-test --strip-components=1 --no-same-owner
rm -f /tmp/etcd-${ETCD_VER}-linux-amd64.tar.gz

/tmp/etcd-download-test/etcd --version
/tmp/etcd-download-test/etcdctl version
/tmp/etcd-download-test/etcdutl version

# start a local etcd server
/tmp/etcd-download-test/etcd

# write,read to etcd
/tmp/etcd-download-test/etcdctl --endpoints=localhost:2379 put foo bar
/tmp/etcd-download-test/etcdctl --endpoints=localhost:2379 get foo
```

###### macOS (Darwin)

```sh
ETCD_VER=v3.7.3

# choose either URL
GOOGLE_URL=https://storage.googleapis.com/etcd
GITHUB_URL=https://github.com/etcd-io/etcd/releases/download
DOWNLOAD_URL=${GOOGLE_URL}

rm -f /tmp/etcd-${ETCD_VER}-darwin-amd64.zip
rm -rf /tmp/etcd-download-test && mkdir -p /tmp/etcd-download-test

curl -L ${DOWNLOAD_URL}/${ETCD_VER}/etcd-${ETCD_VER}-darwin-amd64.zip -o /tmp/etcd-${ETCD_VER}-darwin-amd64.zip
unzip /tmp/etcd-${ETCD_VER}-darwin-amd64.zip -d /tmp && rm -f /tmp/etcd-${ETCD_VER}-darwin-amd64.zip
mv /tmp/etcd-${ETCD_VER}-darwin-amd64/* /tmp/etcd-download-test && rm -rf mv /tmp/etcd-${ETCD_VER}-darwin-amd64

/tmp/etcd-download-test/etcd --version
/tmp/etcd-download-test/etcdctl version
/tmp/etcd-download-test/etcdutl version
```

###### Docker

etcd uses [`gcr.io/etcd-development/etcd`](https://gcr.io/etcd-development/etcd) as a primary container registry, and [`quay.io/coreos/etcd`](https://quay.io/coreos/etcd) as secondary.

```sh
ETCD_VER=v3.7.3

rm -rf /tmp/etcd-data.tmp && mkdir -p /tmp/etcd-data.tmp && \
docker rmi gcr.io/etcd-development/etcd:${ETCD_VER} || true && \
docker run \
-p 2379:2379 \
-p 2380:2380 \
--mount type=bind,source=/tmp/etcd-data.tmp,destination=/etcd-data \
--name etcd-gcr-${ETCD_VER} \
gcr.io/etcd-development/etcd:${ETCD_VER} \
/usr/local/bin/etcd \
--name s1 \
--data-dir /etcd-data \
--listen-client-urls http://0.0.0.0:2379 \
--advertise-client-urls http://0.0.0.0:2379 \
--listen-peer-urls http://0.0.0.0:2380 \
--initial-advertise-peer-urls http://0.0.0.0:2380 \
--initial-cluster s1=http://0.0.0.0:2380 \
--initial-cluster-token tkn \
--initial-cluster-state new \
--log-level info \
--logger zap \
--log-outputs stderr

docker exec etcd-gcr-${ETCD_VER} /usr/local/bin/etcd --version
docker exec etcd-gcr-${ETCD_VER} /usr/local/bin/etcdctl version
docker exec etcd-gcr-${ETCD_VER} /usr/local/bin/etcdutl version
docker exec etcd-gcr-${ETCD_VER} /usr/local/bin/etcdctl endpoint health
docker exec etcd-gcr-${ETCD_VER} /usr/local/bin/etcdctl put foo bar
docker exec etcd-gcr-${ETCD_VER} /usr/local/bin/etcdctl get foo
```