diff --git a/multicluster/charts/linkerd-multicluster/templates/link-crd.yaml b/multicluster/charts/linkerd-multicluster/templates/link-crd.yaml
index e2b8a0c7a3fc6..d24eb02d18c4a 100644
--- a/multicluster/charts/linkerd-multicluster/templates/link-crd.yaml
+++ b/multicluster/charts/linkerd-multicluster/templates/link-crd.yaml
@@ -158,6 +158,7 @@ spec:
                     type: string
                   period:
                     description: Interval in between probe requests
+                    format: duration
                     type: string
                   port:
                     description: Port of remote gateway health endpoint
diff --git a/multicluster/cmd/link.go b/multicluster/cmd/link.go
index 045d2d5070578..117af4cb97324 100644
--- a/multicluster/cmd/link.go
+++ b/multicluster/cmd/link.go
@@ -7,7 +7,9 @@ import (
 	"fmt"
 	"os"
 	"path"
+	"strconv"
 	"strings"
+	"time"
 
 	"github.com/linkerd/linkerd2/controller/gen/apis/link/v1alpha2"
 	"github.com/linkerd/linkerd2/multicluster/static"
@@ -599,10 +601,21 @@ func extractProbeSpec(gateway *corev1.Service) (v1alpha2.ProbeSpec, error) {
 		return v1alpha2.ProbeSpec{}, err
 	}
 
+	// the `mirror.linkerd.io/probe-period` annotation is initialized with a
+	// default value of "3", but we require a duration-formatted string. So we
+	// perform the conversion, if required.
+	period := gateway.Annotations[k8s.GatewayProbePeriod]
+	if secs, err := strconv.ParseInt(period, 10, 64); err == nil {
+		dur := time.Duration(secs) * time.Second
+		period = dur.String()
+	} else if _, err := time.ParseDuration(period); err != nil {
+		return v1alpha2.ProbeSpec{}, fmt.Errorf("could not parse probe period: %w", err)
+	}
+
 	return v1alpha2.ProbeSpec{
 		Path:   path,
 		Port:   fmt.Sprintf("%d", port),
-		Period: gateway.Annotations[k8s.GatewayProbePeriod],
+		Period: period,
 	}, nil
 }
 
diff --git a/multicluster/cmd/testdata/install_default.golden b/multicluster/cmd/testdata/install_default.golden
index 32b4e1aea736e..ec7610c0aa543 100644
--- a/multicluster/cmd/testdata/install_default.golden
+++ b/multicluster/cmd/testdata/install_default.golden
@@ -396,6 +396,7 @@ spec:
                     type: string
                   period:
                     description: Interval in between probe requests
+                    format: duration
                     type: string
                   port:
                     description: Port of remote gateway health endpoint
diff --git a/multicluster/cmd/testdata/install_ha.golden b/multicluster/cmd/testdata/install_ha.golden
index 88488f7879cd5..cb2a4b747a48c 100644
--- a/multicluster/cmd/testdata/install_ha.golden
+++ b/multicluster/cmd/testdata/install_ha.golden
@@ -468,6 +468,7 @@ spec:
                     type: string
                   period:
                     description: Interval in between probe requests
+                    format: duration
                     type: string
                   port:
                     description: Port of remote gateway health endpoint
diff --git a/multicluster/cmd/testdata/install_psp.golden b/multicluster/cmd/testdata/install_psp.golden
index 7a91e393f025b..0542a4033f3a8 100644
--- a/multicluster/cmd/testdata/install_psp.golden
+++ b/multicluster/cmd/testdata/install_psp.golden
@@ -430,6 +430,7 @@ spec:
                     type: string
                   period:
                     description: Interval in between probe requests
+                    format: duration
                     type: string
                   port:
                     description: Port of remote gateway health endpoint
diff --git a/multicluster/service-mirror/probe_worker.go b/multicluster/service-mirror/probe_worker.go
index 42e9989f19342..09f10940a6ccc 100644
--- a/multicluster/service-mirror/probe_worker.go
+++ b/multicluster/service-mirror/probe_worker.go
@@ -70,12 +70,11 @@ func (pw *ProbeWorker) run() {
 		pw.log.Error("Probe spec is nil")
 		return
 	}
-	probeTickerPeriodSeconds, err := strconv.ParseInt(pw.probeSpec.Period, 10, 64)
+	probeTickerPeriod, err := time.ParseDuration(pw.probeSpec.Period)
 	if err != nil {
 		pw.log.Errorf("could not parse probe period: %s", err)
 		return
 	}
-	probeTickerPeriod := time.Duration(probeTickerPeriodSeconds) * time.Second
 	maxJitter := probeTickerPeriod / 10 // max jitter is 10% of period
 	probeTicker := NewTicker(probeTickerPeriod, maxJitter)
 	defer probeTicker.Stop()