diff --git a/cmd/boulder-wfe2/main.go b/cmd/boulder-wfe2/main.go
index d7c796706ce5..70b545c1c11b 100644
--- a/cmd/boulder-wfe2/main.go
+++ b/cmd/boulder-wfe2/main.go
@@ -160,11 +160,11 @@ type Config struct {
 		}
 
 		// MaxNames is the maximum number of subjectAltNames in a single cert.
-		// The value supplied MUST be greater than 0 and no more than 100,
+		// The value supplied SHOULD be greater than 0 and no more than 100,
 		// defaults to 100. These limits are per section 7.1 of our combined
 		// CP/CPS, under "DV-SSL Subscriber Certificate". The value must match
 		// the CA and RA configurations.
-		MaxNames int `validate:"required,min=1,max=100"`
+		MaxNames int `validate:"max=100"`
 	}
 
 	Syslog        cmd.SyslogConfig
@@ -307,7 +307,7 @@ func main() {
 		c.WFE.DebugAddr = *debugAddr
 	}
 	maxNames := c.WFE.MaxNames
-	if maxNames == 0 {
+	if maxNames <= 0 {
 		// Default to 100 names per cert.
 		maxNames = 100
 	}