}
		}
	}
	errs = AppendErrors(errs, validateSidecarOrGatewayHostnamePart(parts[1], isGateway))
	return
}

// ValidateIPSubnet checks that a string is in "CIDR notation" or "Dot-decimal notation"
func ValidateIPSubnet(subnet string) error {
	// We expect a string in "CIDR notation" or "Dot-decimal notation"
	// E.g., a.b.c.d/xx form or just a.b.c.d or 2001:1::1/64

			ok:     true,
		},
		{
			name:   "invalid ipv6 subnet",
			subnet: "2001:1::1/132",
			ok:     false,
		},
	}

	for _, tt := range tests {
		if err := ValidateIPSubnet(tt.subnet); err != nil {
			if tt.ok {
				t.Errorf("test: \"%s\" expected to succeed but failed with error: %+v", tt.name, err)
			}
		} else {
			if !tt.ok {