Do it in post

kubernetes-sigs · Feb 15, 2023 · 1964100 · 1964100
1 parent 33c4eaf
commit 1964100
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Showing 3 changed files with 16 additions and 19 deletions.
diff --git a/images/base/files/usr/local/bin/entrypoint b/images/base/files/usr/local/bin/entrypoint
@@ -417,7 +417,20 @@ enable_network_magic(){
 
   # now we can ensure that DNS is configured to use our IP
   cp /etc/resolv.conf /etc/resolv.conf.original
-  sed -e "s/${docker_embedded_dns_ip}/${docker_host_ip}/g" /etc/resolv.conf.original >/etc/resolv.conf
+  replaced="$(sed -e "s/${docker_embedded_dns_ip}/${docker_host_ip}/g" /etc/resolv.conf.original)"
+  if [[ "${KIND_DNS_SEARCH+x}" == "" ]]; then
+    # No DNS search set, just pass through as is
+    echo "$replaced" >/etc/resolv.conf
+  elif [[ -z "$KIND_DNS_SEARCH" ]]; then
+    # Empty search - remove all current search clauses
+    echo "$replaced" | grep -v "^search" >/etc/resolv.conf
+  else
+    # Search set - remove all current search clauses, and add the configured search
+    {
+      echo "search $KIND_DNS_SEARCH";
+      echo "$replaced" | grep -v "^search";
+    } >/etc/resolv.conf
+  fi
 
   local files_to_update=(
     /etc/kubernetes/manifests/etcd.yaml

diff --git a/pkg/cluster/internal/providers/docker/provision.go b/pkg/cluster/internal/providers/docker/provision.go
@@ -201,18 +201,7 @@ func commonArgs(cluster string, cfg *config.Cluster, networkName string, nodeNam
 	}
 
 	if cfg.Networking.DNSSearch != nil {
-		if len(*cfg.Networking.DNSSearch) == 0 {
-			return nil, errors.New("docker provider requires a non-empty dnsSearch")
-		}
-		for _, s := range *cfg.Networking.DNSSearch {
-			args = append(args, "--dns-search", s)
-		}
-		args = append(args, "--dns", "8.8.8.8")
-		args = append(args, "--dns", "8.8.4.4")
-		if config.ClusterHasIPv6(cfg) {
-			args = append(args, "--dns", "2001:4860:4860::8888")
-			args = append(args, "--dns", "2001:4860:4860::8844")
-		}
+		args = append(args, "-e", "KIND_DNS_SEARCH="+strings.Join(*cfg.Networking.DNSSearch, " "))
 	}
 
 	return args, nil

diff --git a/pkg/cluster/internal/providers/podman/provision.go b/pkg/cluster/internal/providers/podman/provision.go
@@ -165,12 +165,7 @@ func commonArgs(cfg *config.Cluster, networkName string, nodeNames []string) ([]
 	}
 
 	if cfg.Networking.DNSSearch != nil {
-		if len(*cfg.Networking.DNSSearch) == 0 {
-			args = append(args, "--dns-search", "")
-		}
-		for _, s := range *cfg.Networking.DNSSearch {
-			args = append(args, "--dns-search", s)
-		}
+		args = append(args, "-e", "KIND_DNS_SEARCH="+strings.Join(*cfg.Networking.DNSSearch, " "))
 	}
 
 	return args, nil