diff --git a/components/egress/docs/opentelemetry.md b/components/egress/docs/opentelemetry.md index a7830def8..7f2d738ee 100644 --- a/components/egress/docs/opentelemetry.md +++ b/components/egress/docs/opentelemetry.md @@ -91,10 +91,47 @@ Metric export is enabled only when at least one OTLP endpoint is set. If both are unset, egress keeps metrics local (no OTLP export). +### Automatic Egress Allow Rule + +When an OTLP destination is configured — the endpoint env vars below, or the +exporter fallback node IP (`HOST_IP` / `/etc/hostinfo`) when both are unset — +egress automatically injects an always-allow egress rule for that host +(domain or IP, any port), so telemetry export works under the default deny-all +policy without manually managing allowlist rules. This also covers the egress +sidecar's own metric export, which shares the sandbox network namespace and +would otherwise be blocked by its own egress chain. + +- The rule follows the standard precedence: `OTEL_EXPORTER_OTLP_METRICS_ENDPOINT` + wins over `OTEL_EXPORTER_OTLP_ENDPOINT`; the fallback node IP applies only + when neither is set. A set-but-invalid endpoint never falls back (the + exporter does not either), so no rule is injected in that case. +- The endpoint must be a URL (`https://host:4318/v1/metrics`) — the + `otlpmetrichttp` env-var form. Bare `host:port` or `host` values are not + accepted (the exporter parses them as opaque URLs with an empty host); a + trailing root dot on FQDNs is trimmed to match DNS policy normalization. +- The rule lives in the always-allow layer: it survives user `POST`/`PATCH`/`DELETE` + policy updates and always-rule file reloads. Operators can still block the target + with `deny.always`, which takes precedence. +- Rules are host-scoped (any port), matching the egress rule model; ports are not + enforced per rule. + +> **Note**: use a fully-qualified service name or an IP in the endpoint. +> Single-label names (e.g. `otel-collector`) are subject to resolver +> search-domain expansion, and the deny-all DNS proxy answers the expanded +> names (e.g. `otel-collector..svc.cluster.local`) with NXDOMAIN without +> falling back to the bare name, so the auto-generated exact-host allow rule +> would not be reached. + ### Minimal Example ```bash -export OTEL_EXPORTER_OTLP_METRICS_ENDPOINT="http://otel-collector:4318" +export OTEL_EXPORTER_OTLP_METRICS_ENDPOINT="http://otel-collector.sandbox.svc.cluster.local:4318" +``` + +An IP endpoint works as well: + +```bash +export OTEL_EXPORTER_OTLP_METRICS_ENDPOINT="http://10.0.0.5:4318" ``` ### Service Name diff --git a/components/egress/main.go b/components/egress/main.go index d74c98c23..d6aeb6c79 100644 --- a/components/egress/main.go +++ b/components/egress/main.go @@ -78,6 +78,7 @@ func main() { if err != nil { log.Fatalf("failed to load always allow/deny rule files: %v", err) } + alwaysAllow = withTelemetryAllow(alwaysAllow) allowIPs := allowIps() mode := parseMode() diff --git a/components/egress/policy_server.go b/components/egress/policy_server.go index ac510f3cc..b6a05ff1e 100644 --- a/components/egress/policy_server.go +++ b/components/egress/policy_server.go @@ -713,6 +713,8 @@ func (s *policyServer) reloadAlwaysRules() (bool, error) { if !changed { return false, nil } + allow = withTelemetryAllow(allow) + s.setAlwaysRules(deny, allow) s.proxy.UpdateAlwaysRules(deny, allow) return true, nil } diff --git a/components/egress/telemetry_allow.go b/components/egress/telemetry_allow.go new file mode 100644 index 000000000..1c8f3b298 --- /dev/null +++ b/components/egress/telemetry_allow.go @@ -0,0 +1,67 @@ +// Copyright 2026 Alibaba Group Holding Ltd. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package main + +import ( + "github.com/alibaba/opensandbox/egress/pkg/log" + "github.com/alibaba/opensandbox/egress/pkg/policy" + inttelemetry "github.com/alibaba/opensandbox/internal/telemetry" +) + +// telemetryAllowRules returns an always-allow egress rule for the OTLP +// destination the exporter will dial, so metric export works under the default +// deny-all policy without operator-provided allowlist rules. The destination +// is the endpoint env var +// (OTEL_EXPORTER_OTLP_METRICS_ENDPOINT / OTEL_EXPORTER_OTLP_ENDPOINT, URL form +// as required by otlpmetrichttp) or, only when neither is set, the exporter +// fallback node IP (HOST_IP / /etc/hostinfo). A set-but-unparseable endpoint +// is not treated as unset: the exporter never falls back to the node IP in +// that case, so no rule is injected. The rule targets the host (any port), +// matching the egress rule model. Operators can still block the target via +// deny.always, which takes precedence. Returns nil when no OTLP destination +// is configured. +func telemetryAllowRules() []policy.EgressRule { + host, port, ok := inttelemetry.OTLPEndpointHostPort() + if !ok { + if inttelemetry.OTLPEndpointEnvSet() { + log.Warnf("telemetry: configured OTLP endpoint is not a valid URL; skipping auto egress allow") + return nil + } + host, port, ok = inttelemetry.OTLPEndpointFallbackHostPort() + } + if !ok { + return nil + } + rule, err := policy.ParseValidatedEgressRule(policy.ActionAllow, host) + if err != nil { + log.Warnf("telemetry: skipping auto egress allow for OTLP endpoint host %q: %v", host, err) + return nil + } + log.Infof("telemetry: auto-allowing egress to OTLP endpoint %s:%s (deny.always can override)", host, port) + return []policy.EgressRule{rule} +} + +// withTelemetryAllow appends the auto-generated OTLP allow rule(s) to the +// always-allow list so every effective-policy merge (startup, policy updates, +// always-file reloads) keeps telemetry egress open. +func withTelemetryAllow(allow []policy.EgressRule) []policy.EgressRule { + rules := telemetryAllowRules() + if len(rules) == 0 { + return allow + } + out := make([]policy.EgressRule, 0, len(allow)+len(rules)) + out = append(out, allow...) + return append(out, rules...) +} diff --git a/components/egress/telemetry_allow_test.go b/components/egress/telemetry_allow_test.go new file mode 100644 index 000000000..cce684944 --- /dev/null +++ b/components/egress/telemetry_allow_test.go @@ -0,0 +1,128 @@ +// Copyright 2026 Alibaba Group Holding Ltd. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package main + +import ( + "testing" + + "github.com/alibaba/opensandbox/egress/pkg/policy" + "github.com/stretchr/testify/require" +) + +func TestTelemetryAllowRulesUnconfigured(t *testing.T) { + t.Setenv("OTEL_EXPORTER_OTLP_METRICS_ENDPOINT", "") + t.Setenv("OTEL_EXPORTER_OTLP_ENDPOINT", "") + require.Nil(t, telemetryAllowRules()) + + existing := []policy.EgressRule{{Action: policy.ActionAllow, Target: "a.example.com"}} + require.Equal(t, existing, withTelemetryAllow(existing), "no telemetry rules must not mutate the input") +} + +func TestTelemetryAllowRulesFromMetricsEndpoint(t *testing.T) { + t.Setenv("OTEL_EXPORTER_OTLP_METRICS_ENDPOINT", "https://collector.example:4318/v1/metrics") + t.Setenv("OTEL_EXPORTER_OTLP_ENDPOINT", "") + rules := telemetryAllowRules() + require.Len(t, rules, 1) + require.Equal(t, policy.ActionAllow, rules[0].Action) + require.Equal(t, "collector.example", rules[0].Target) + + merged := policy.MergeAlwaysOverlay(policy.DefaultDenyPolicy(), nil, rules) + require.Equal(t, policy.ActionAllow, merged.Evaluate("collector.example."), "domain rule must allow DNS resolution") + allowV4, allowV6, _, _ := merged.StaticIPSets() + require.Empty(t, allowV4) + require.Empty(t, allowV6) +} + +func TestTelemetryAllowRulesFallbackEndpoint(t *testing.T) { + t.Setenv("OTEL_EXPORTER_OTLP_METRICS_ENDPOINT", "") + t.Setenv("OTEL_EXPORTER_OTLP_ENDPOINT", "https://otel-collector:4318") + rules := telemetryAllowRules() + require.Len(t, rules, 1) + require.Equal(t, "otel-collector", rules[0].Target) +} + +func TestTelemetryAllowRulesFallbackNodeIP(t *testing.T) { + t.Setenv("OTEL_EXPORTER_OTLP_METRICS_ENDPOINT", "") + t.Setenv("OTEL_EXPORTER_OTLP_ENDPOINT", "") + t.Setenv("HOST_IP", "10.0.0.9") + rules := telemetryAllowRules() + require.Len(t, rules, 1) + require.Equal(t, "10.0.0.9", rules[0].Target) + + merged := policy.MergeAlwaysOverlay(policy.DefaultDenyPolicy(), nil, rules) + allowV4, allowV6, _, _ := merged.StaticIPSets() + require.Equal(t, []string{"10.0.0.9"}, allowV4, "fallback node IP must land in the static allow v4 set") + require.Empty(t, allowV6) +} + +func TestTelemetryAllowRulesFQDNTrailingDot(t *testing.T) { + t.Setenv("OTEL_EXPORTER_OTLP_METRICS_ENDPOINT", "http://otel-collector.ns.svc.cluster.local.:4318") + t.Setenv("OTEL_EXPORTER_OTLP_ENDPOINT", "") + rules := telemetryAllowRules() + require.Len(t, rules, 1) + require.Equal(t, "otel-collector.ns.svc.cluster.local", rules[0].Target) + + merged := policy.MergeAlwaysOverlay(policy.DefaultDenyPolicy(), nil, rules) + require.Equal(t, policy.ActionAllow, merged.Evaluate("otel-collector.ns.svc.cluster.local."), "trailing-dot host must match DNS policy normalization") + require.Equal(t, policy.ActionDeny, merged.Evaluate("other.ns.svc.cluster.local.")) +} + +func TestTelemetryAllowRulesIPEndpoint(t *testing.T) { + t.Setenv("OTEL_EXPORTER_OTLP_METRICS_ENDPOINT", "http://10.0.0.5:4317") + t.Setenv("OTEL_EXPORTER_OTLP_ENDPOINT", "") + rules := telemetryAllowRules() + require.Len(t, rules, 1) + require.Equal(t, "10.0.0.5", rules[0].Target) + + merged := policy.MergeAlwaysOverlay(policy.DefaultDenyPolicy(), nil, rules) + allowV4, allowV6, _, _ := merged.StaticIPSets() + require.Equal(t, []string{"10.0.0.5"}, allowV4, "IP target must land in the static allow v4 set") + require.Empty(t, allowV6) +} + +func TestTelemetryAllowRulesInvalidEndpoint(t *testing.T) { + t.Setenv("OTEL_EXPORTER_OTLP_METRICS_ENDPOINT", "http://") + t.Setenv("OTEL_EXPORTER_OTLP_ENDPOINT", "") + require.Nil(t, telemetryAllowRules()) +} + +func TestTelemetryAllowRulesInvalidEndpointSkipsNodeIPFallback(t *testing.T) { + t.Setenv("OTEL_EXPORTER_OTLP_METRICS_ENDPOINT", "http://") + t.Setenv("OTEL_EXPORTER_OTLP_ENDPOINT", "") + t.Setenv("HOST_IP", "10.0.0.9") + require.Nil(t, telemetryAllowRules(), "configured-but-invalid endpoint must not open node-IP egress") + + t.Setenv("OTEL_EXPORTER_OTLP_METRICS_ENDPOINT", "") + rules := telemetryAllowRules() + require.Len(t, rules, 1, "unset endpoint should fall back to the node IP") + require.Equal(t, "10.0.0.9", rules[0].Target) +} + +func TestWithTelemetryAllowAppends(t *testing.T) { + t.Setenv("OTEL_EXPORTER_OTLP_METRICS_ENDPOINT", "https://collector.example:4318") + t.Setenv("OTEL_EXPORTER_OTLP_ENDPOINT", "") + existingRule, err := policy.ParseValidatedEgressRule(policy.ActionAllow, "a.example.com") + require.NoError(t, err) + existing := []policy.EgressRule{existingRule} + rules := withTelemetryAllow(existing) + require.Len(t, rules, 2) + require.Equal(t, "a.example.com", rules[0].Target) + require.Equal(t, "collector.example", rules[1].Target) + + merged := policy.MergeAlwaysOverlay(policy.DefaultDenyPolicy(), nil, rules) + require.Equal(t, policy.ActionDeny, merged.Evaluate("other.example.com.")) + require.Equal(t, policy.ActionAllow, merged.Evaluate("a.example.com.")) + require.Equal(t, policy.ActionAllow, merged.Evaluate("collector.example.")) +} diff --git a/components/execd/pkg/web/controller/pty_ws.go b/components/execd/pkg/web/controller/pty_ws.go index d369884d6..b444ee309 100644 --- a/components/execd/pkg/web/controller/pty_ws.go +++ b/components/execd/pkg/web/controller/pty_ws.go @@ -500,38 +500,60 @@ func ptyViewerClientReadLoop( switch msgType { case websocket.BinaryMessage: - if len(data) > 0 && data[0] == model.BinStdin { - if !readOnlyError() { - return - } + if !ptyViewerHandleBinaryMessage(data, readOnlyError) { + return } case websocket.TextMessage: - var frame model.ClientFrame - if json.Unmarshal(data, &frame) != nil { - continue - } - switch frame.Type { - case "stdin", "signal", "resize": - if !readOnlyError() { - return - } - case "ping": - if err := writeJSON(model.ServerFrame{Type: "pong"}); err != nil { - cancelOnce() - } - default: - if err := writeJSON(model.ServerFrame{ - Type: "error", - Code: model.WSErrCodeInvalidFrame, - Error: fmt.Sprintf("unknown frame type %q", frame.Type), - }); err != nil { - cancelOnce() - } + if !ptyViewerHandleTextMessage(data, writeJSON, readOnlyError, cancelOnce) { + return } } } } +// ptyViewerHandleBinaryMessage reports stdin payloads on a read-only viewer; +// returns false when the read loop should exit. +func ptyViewerHandleBinaryMessage(data []byte, readOnlyError func() bool) bool { + if len(data) > 0 && data[0] == model.BinStdin { + return readOnlyError() + } + return true +} + +// ptyViewerHandleTextMessage handles client frames on a read-only viewer; +// returns false when the read loop should exit. +func ptyViewerHandleTextMessage(data []byte, writeJSON func(any) error, readOnlyError func() bool, cancelOnce func()) bool { + var frame model.ClientFrame + if json.Unmarshal(data, &frame) != nil { + return true + } + switch frame.Type { + case "stdin", "signal", "resize": + return readOnlyError() + case "ping": + ptyViewerReplyPong(writeJSON, cancelOnce) + default: + ptyViewerReplyInvalidFrame(writeJSON, cancelOnce, frame.Type) + } + return true +} + +func ptyViewerReplyPong(writeJSON func(any) error, cancelOnce func()) { + if err := writeJSON(model.ServerFrame{Type: "pong"}); err != nil { + cancelOnce() + } +} + +func ptyViewerReplyInvalidFrame(writeJSON func(any) error, cancelOnce func(), frameType string) { + if err := writeJSON(model.ServerFrame{ + Type: "error", + Code: model.WSErrCodeInvalidFrame, + Error: fmt.Sprintf("unknown frame type %q", frameType), + }); err != nil { + cancelOnce() + } +} + // ptyPingLoop sends periodic WebSocket pings until cancelCh is closed. func ptyPingLoop(conn *websocket.Conn, connMu *sync.Mutex, cancelCh <-chan struct{}, cancelOnce func()) { t := time.NewTicker(wsPingInterval) diff --git a/components/internal/telemetry/endpoint.go b/components/internal/telemetry/endpoint.go new file mode 100644 index 000000000..00ae587c9 --- /dev/null +++ b/components/internal/telemetry/endpoint.go @@ -0,0 +1,89 @@ +// Copyright 2026 Alibaba Group Holding Ltd. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package telemetry + +import ( + "net/url" + "strings" +) + +// OTLPEndpointHostPort returns the host and port of the configured OTLP +// endpoint. Endpoint precedence matches the exporters: +// OTEL_EXPORTER_OTLP_METRICS_ENDPOINT, then OTEL_EXPORTER_OTLP_ENDPOINT. +// The value must be a URL (scheme://host[:port][/path]), matching the +// otlpmetrichttp env-var form; bare host:port or host values are invalid +// because the exporter parses them as opaque URLs with an empty host. +// A missing port falls back to the scheme default (https->443, http->80). +// Domain hosts are returned without the trailing dot, matching DNS policy +// normalization. ok is false when no endpoint is configured or it cannot +// be parsed. +func OTLPEndpointHostPort() (host, port string, ok bool) { + raw := otlpEndpointFromEnv() + if raw == "" { + return "", "", false + } + return parseOTLPEndpoint(raw) +} + +// OTLPEndpointEnvSet reports whether any OTEL endpoint env var is non-blank, +// regardless of whether it parses. Callers that also use +// OTLPEndpointFallbackHostPort need this to distinguish "unset" from +// "configured but invalid": the exporter never falls back to the node IP once +// an endpoint env var is set, so neither should the auto-allow logic. +func OTLPEndpointEnvSet() bool { + return otlpEndpointFromEnv() != "" +} + +// OTLPEndpointFallbackHostPort returns the exporter fallback destination used +// only when no OTEL endpoint env var is set: the resolved node IP +// (HOST_IP, then /etc/hostinfo) on the default OTLP/HTTP port 4318. ok is +// false when no node IP can be resolved. +func OTLPEndpointFallbackHostPort() (host, port string, ok bool) { + ip, ok := resolveNodeIP() + if !ok { + return "", "", false + } + return ip, otlpHTTPPort, true +} + +func parseOTLPEndpoint(raw string) (host, port string, ok bool) { + raw = strings.TrimSpace(raw) + if !strings.Contains(raw, "://") { + return "", "", false + } + u, err := url.Parse(raw) + if err != nil { + return "", "", false + } + host = strings.TrimRight(strings.TrimSpace(u.Hostname()), ".") + if host == "" { + return "", "", false + } + port = u.Port() + if port == "" { + port = defaultPortForScheme(u.Scheme) + } + return host, port, true +} + +func defaultPortForScheme(scheme string) string { + switch strings.ToLower(scheme) { + case "https": + return "443" + case "http": + return "80" + } + return "" +} diff --git a/components/internal/telemetry/endpoint_test.go b/components/internal/telemetry/endpoint_test.go new file mode 100644 index 000000000..d4ebbfe73 --- /dev/null +++ b/components/internal/telemetry/endpoint_test.go @@ -0,0 +1,118 @@ +// Copyright 2026 Alibaba Group Holding Ltd. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package telemetry + +import "testing" + +func TestParseOTLPEndpoint(t *testing.T) { + cases := []struct { + name string + raw string + host string + port string + ok bool + }{ + {name: "empty", raw: "", ok: false}, + {name: "whitespace", raw: " ", ok: false}, + {name: "url with port and path", raw: "https://collector.example:4318/v1/metrics", host: "collector.example", port: "4318", ok: true}, + {name: "url without port", raw: "https://collector.example/v1/metrics", host: "collector.example", port: "443", ok: true}, + {name: "http url without port", raw: "http://collector.example/v1/metrics", host: "collector.example", port: "80", ok: true}, + {name: "ip url", raw: "http://10.0.0.1:4317", host: "10.0.0.1", port: "4317", ok: true}, + {name: "ipv6 url", raw: "http://[::1]:4318/v1/metrics", host: "::1", port: "4318", ok: true}, + {name: "host port without scheme", raw: "collector.example:4318", ok: false}, + {name: "ip port without scheme", raw: "10.0.0.1:4318", ok: false}, + {name: "bare host", raw: "collector.example", ok: false}, + {name: "bare ip", raw: "10.0.0.1", ok: false}, + {name: "fqdn url trailing dot", raw: "http://otel-collector.ns.svc.cluster.local.:4318", host: "otel-collector.ns.svc.cluster.local", port: "4318", ok: true}, + {name: "fqdn trailing dot without scheme", raw: "otel-collector.ns.svc.cluster.local.:4318", ok: false}, + {name: "bare fqdn trailing dot", raw: "collector.example.", ok: false}, + {name: "scheme only", raw: "http://", ok: false}, + {name: "malformed url", raw: "https://:443", ok: false}, + } + for _, tc := range cases { + t.Run(tc.name, func(t *testing.T) { + host, port, ok := parseOTLPEndpoint(tc.raw) + if ok != tc.ok { + t.Fatalf("parseOTLPEndpoint(%q) ok=%v, want %v", tc.raw, ok, tc.ok) + } + if host != tc.host || port != tc.port { + t.Fatalf("parseOTLPEndpoint(%q) = (%q, %q), want (%q, %q)", tc.raw, host, port, tc.host, tc.port) + } + }) + } +} + +func TestOTLPEndpointHostPortPrecedence(t *testing.T) { + t.Setenv(envOTLPMetricsEndpoint, "") + t.Setenv(envOTLPEndpoint, "") + host, _, ok := OTLPEndpointHostPort() + if ok { + t.Fatal("expected no endpoint when both env vars are unset") + } + if host != "" { + t.Fatalf("expected empty host, got %q", host) + } + + t.Setenv(envOTLPEndpoint, "https://fallback.example:4318") + host, port, ok := OTLPEndpointHostPort() + if !ok || host != "fallback.example" || port != "4318" { + t.Fatalf("fallback endpoint parsed as (%q, %q, %v)", host, port, ok) + } + + t.Setenv(envOTLPMetricsEndpoint, "https://primary.example:4317/v1/metrics") + host, port, ok = OTLPEndpointHostPort() + if !ok || host != "primary.example" || port != "4317" { + t.Fatalf("metrics endpoint should win; parsed as (%q, %q, %v)", host, port, ok) + } + + t.Setenv(envOTLPMetricsEndpoint, " ") + host, port, ok = OTLPEndpointHostPort() + if !ok || host != "fallback.example" || port != "4318" { + t.Fatalf("blank metrics endpoint should fall back; parsed as (%q, %q, %v)", host, port, ok) + } +} + +func TestOTLPEndpointEnvSet(t *testing.T) { + t.Setenv(envOTLPMetricsEndpoint, "") + t.Setenv(envOTLPEndpoint, "") + if OTLPEndpointEnvSet() { + t.Fatal("expected env unset") + } + + t.Setenv(envOTLPEndpoint, "http://") + if !OTLPEndpointEnvSet() { + t.Fatal("expected env set even when unparseable") + } + + t.Setenv(envOTLPEndpoint, "") + t.Setenv(envOTLPMetricsEndpoint, "https://collector.example:4318") + if !OTLPEndpointEnvSet() { + t.Fatal("expected metrics endpoint env set") + } +} + +func TestOTLPEndpointFallbackHostPort(t *testing.T) { + t.Setenv(envHostIP, "10.0.0.9") + host, port, ok := OTLPEndpointFallbackHostPort() + if !ok || host != "10.0.0.9" || port != otlpHTTPPort { + t.Fatalf("fallback from HOST_IP parsed as (%q, %q, %v)", host, port, ok) + } + + t.Setenv(envHostIP, " ") + host, _, ok = OTLPEndpointFallbackHostPort() + if ok { + t.Fatalf("expected no fallback without a resolvable node IP, got %q", host) + } +}