diff --git a/CHANGELOG.md b/CHANGELOG.md
index a0f0cca16..99e8ffe56 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -63,6 +63,8 @@ should now look like:
 - [#1460](https://github.com/influxdata/telegraf/issues/1460): Remove PID from procstat plugin to fix cardinality issues.
 - [#1427](https://github.com/influxdata/telegraf/issues/1427): Cassandra input: version 2.x "column family" fix.
 - [#1463](https://github.com/influxdata/telegraf/issues/1463): Shared WaitGroup in Exec plugin
+- [#1436](https://github.com/influxdata/telegraf/issues/1436): logparser: honor modifiers in "pattern" config.
+- [#1418](https://github.com/influxdata/telegraf/issues/1418): logparser: error and exit on file permissions/missing errors.
 
 ## v1.0 beta 2 [2016-06-21]
 
diff --git a/plugins/inputs/logparser/grok/grok.go b/plugins/inputs/logparser/grok/grok.go
index 16e62b223..d8691d7b9 100644
--- a/plugins/inputs/logparser/grok/grok.go
+++ b/plugins/inputs/logparser/grok/grok.go
@@ -53,7 +53,12 @@ var (
 )
 
 type Parser struct {
-	Patterns           []string
+	Patterns []string
+	// namedPatterns is a list of internally-assigned names to the patterns
+	// specified by the user in Patterns.
+	// They will look like:
+	//   GROK_INTERNAL_PATTERN_0, GROK_INTERNAL_PATTERN_1, etc.
+	namedPatterns      []string
 	CustomPatterns     string
 	CustomPatternFiles []string
 	Measurement        string
@@ -98,13 +103,24 @@ func (p *Parser) Compile() error {
 		return err
 	}
 
-	p.CustomPatterns = DEFAULT_PATTERNS + p.CustomPatterns
+	// Give Patterns fake names so that they can be treated as named
+	// "custom patterns"
+	p.namedPatterns = make([]string, len(p.Patterns))
+	for i, pattern := range p.Patterns {
+		name := fmt.Sprintf("GROK_INTERNAL_PATTERN_%d", i)
+		p.CustomPatterns += "\n" + name + " " + pattern + "\n"
+		p.namedPatterns[i] = "%{" + name + "}"
+	}
 
+	// Combine user-supplied CustomPatterns with DEFAULT_PATTERNS and parse
+	// them together as the same type of pattern.
+	p.CustomPatterns = DEFAULT_PATTERNS + p.CustomPatterns
 	if len(p.CustomPatterns) != 0 {
 		scanner := bufio.NewScanner(strings.NewReader(p.CustomPatterns))
 		p.addCustomPatterns(scanner)
 	}
 
+	// Parse any custom pattern files supplied.
 	for _, filename := range p.CustomPatternFiles {
 		file, err := os.Open(filename)
 		if err != nil {
@@ -127,7 +143,7 @@ func (p *Parser) ParseLine(line string) (telegraf.Metric, error) {
 	var values map[string]string
 	// the matching pattern string
 	var patternName string
-	for _, pattern := range p.Patterns {
+	for _, pattern := range p.namedPatterns {
 		if values, err = p.g.Parse(pattern, line); err != nil {
 			return nil, err
 		}
diff --git a/plugins/inputs/logparser/grok/grok_test.go b/plugins/inputs/logparser/grok/grok_test.go
index 1181e85ae..295f32609 100644
--- a/plugins/inputs/logparser/grok/grok_test.go
+++ b/plugins/inputs/logparser/grok/grok_test.go
@@ -207,7 +207,7 @@ func TestBuiltinCombinedLogFormat(t *testing.T) {
 
 func TestCompileStringAndParse(t *testing.T) {
 	p := &Parser{
-		Patterns: []string{"%{TEST_LOG_A}", "%{TEST_LOG_B}"},
+		Patterns: []string{"%{TEST_LOG_A}"},
 		CustomPatterns: `
 			DURATION %{NUMBER}[nuµm]?s
 			RESPONSE_CODE %{NUMBER:response_code:tag}
@@ -230,6 +230,41 @@ func TestCompileStringAndParse(t *testing.T) {
 	assert.Equal(t, map[string]string{"response_code": "200"}, metricA.Tags())
 }
 
+func TestCompileErrorsOnInvalidPattern(t *testing.T) {
+	p := &Parser{
+		Patterns: []string{"%{TEST_LOG_A}", "%{TEST_LOG_B}"},
+		CustomPatterns: `
+			DURATION %{NUMBER}[nuµm]?s
+			RESPONSE_CODE %{NUMBER:response_code:tag}
+			RESPONSE_TIME %{DURATION:response_time:duration}
+			TEST_LOG_A %{NUMBER:myfloat:float} %{RESPONSE_CODE} %{IPORHOST:clientip} %{RESPONSE_TIME}
+		`,
+	}
+	assert.Error(t, p.Compile())
+
+	metricA, _ := p.ParseLine(`1.25 200 192.168.1.1 5.432µs`)
+	require.Nil(t, metricA)
+}
+
+func TestParsePatternsWithoutCustom(t *testing.T) {
+	p := &Parser{
+		Patterns: []string{"%{POSINT:ts:ts-epochnano} response_time=%{POSINT:response_time:int} mymetric=%{NUMBER:metric:float}"},
+	}
+	assert.NoError(t, p.Compile())
+
+	metricA, err := p.ParseLine(`1466004605359052000 response_time=20821 mymetric=10890.645`)
+	require.NotNil(t, metricA)
+	assert.NoError(t, err)
+	assert.Equal(t,
+		map[string]interface{}{
+			"response_time": int64(20821),
+			"metric":        float64(10890.645),
+		},
+		metricA.Fields())
+	assert.Equal(t, map[string]string{}, metricA.Tags())
+	assert.Equal(t, time.Unix(0, 1466004605359052000), metricA.Time())
+}
+
 func TestParseEpochNano(t *testing.T) {
 	p := &Parser{
 		Patterns: []string{"%{MYAPP}"},
@@ -413,7 +448,7 @@ func TestParseErrors(t *testing.T) {
 			TEST_LOG_A %{HTTPDATE:ts:ts-httpd} %{WORD:myword:int} %{}
 		`,
 	}
-	assert.NoError(t, p.Compile())
+	assert.Error(t, p.Compile())
 	_, err := p.ParseLine(`[04/Jun/2016:12:41:45 +0100] notnumber 200 192.168.1.1 5.432µs 101`)
 	assert.Error(t, err)
 
diff --git a/plugins/inputs/logparser/logparser.go b/plugins/inputs/logparser/logparser.go
index 4737ace65..6b29ea031 100644
--- a/plugins/inputs/logparser/logparser.go
+++ b/plugins/inputs/logparser/logparser.go
@@ -9,6 +9,7 @@ import (
 	"github.com/hpcloud/tail"
 
 	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/internal/errchan"
 	"github.com/influxdata/telegraf/internal/globpath"
 	"github.com/influxdata/telegraf/plugins/inputs"
 
@@ -110,11 +111,15 @@ func (l *LogParserPlugin) Start(acc telegraf.Accumulator) error {
 	}
 
 	// compile log parser patterns:
+	errChan := errchan.New(len(l.parsers))
 	for _, parser := range l.parsers {
 		if err := parser.Compile(); err != nil {
-			return err
+			errChan.C <- err
 		}
 	}
+	if err := errChan.Error(); err != nil {
+		return err
+	}
 
 	var seek tail.SeekInfo
 	if !l.FromBeginning {
@@ -125,24 +130,25 @@ func (l *LogParserPlugin) Start(acc telegraf.Accumulator) error {
 	l.wg.Add(1)
 	go l.parser()
 
-	var errS string
 	// Create a "tailer" for each file
 	for _, filepath := range l.Files {
 		g, err := globpath.Compile(filepath)
 		if err != nil {
 			log.Printf("ERROR Glob %s failed to compile, %s", filepath, err)
+			continue
 		}
-		for file, _ := range g.Match() {
+		files := g.Match()
+		errChan = errchan.New(len(files))
+		for file, _ := range files {
 			tailer, err := tail.TailFile(file,
 				tail.Config{
-					ReOpen:   true,
-					Follow:   true,
-					Location: &seek,
+					ReOpen:    true,
+					Follow:    true,
+					Location:  &seek,
+					MustExist: true,
 				})
-			if err != nil {
-				errS += err.Error() + " "
-				continue
-			}
+			errChan.C <- err
+
 			// create a goroutine for each "tailer"
 			l.wg.Add(1)
 			go l.receiver(tailer)
@@ -150,10 +156,7 @@ func (l *LogParserPlugin) Start(acc telegraf.Accumulator) error {
 		}
 	}
 
-	if errS != "" {
-		return fmt.Errorf(errS)
-	}
-	return nil
+	return errChan.Error()
 }
 
 // receiver is launched as a goroutine to continuously watch a tailed logfile
@@ -201,8 +204,6 @@ func (l *LogParserPlugin) parser() {
 				if m != nil {
 					l.acc.AddFields(m.Name(), m.Fields(), m.Tags(), m.Time())
 				}
-			} else {
-				log.Printf("Malformed log line in [%s], Error: %s\n", line, err)
 			}
 		}
 	}
diff --git a/plugins/inputs/logparser/logparser_test.go b/plugins/inputs/logparser/logparser_test.go
index 095b627ef..97f33067e 100644
--- a/plugins/inputs/logparser/logparser_test.go
+++ b/plugins/inputs/logparser/logparser_test.go
@@ -37,7 +37,7 @@ func TestGrokParseLogFilesNonExistPattern(t *testing.T) {
 	}
 
 	acc := testutil.Accumulator{}
-	assert.NoError(t, logparser.Start(&acc))
+	assert.Error(t, logparser.Start(&acc))
 
 	time.Sleep(time.Millisecond * 500)
 	logparser.Stop()
@@ -80,6 +80,8 @@ func TestGrokParseLogFiles(t *testing.T) {
 		map[string]string{})
 }
 
+// Test that test_a.log line gets parsed even though we don't have the correct
+// pattern available for test_b.log
 func TestGrokParseLogFilesOneBad(t *testing.T) {
 	thisdir := getCurrentDir()
 	p := &grok.Parser{
@@ -90,11 +92,12 @@ func TestGrokParseLogFilesOneBad(t *testing.T) {
 
 	logparser := &LogParserPlugin{
 		FromBeginning: true,
-		Files:         []string{thisdir + "grok/testdata/*.log"},
+		Files:         []string{thisdir + "grok/testdata/test_a.log"},
 		GrokParser:    p,
 	}
 
 	acc := testutil.Accumulator{}
+	acc.SetDebug(true)
 	assert.NoError(t, logparser.Start(&acc))
 
 	time.Sleep(time.Millisecond * 500)
diff --git a/plugins/inputs/tail/tail.go b/plugins/inputs/tail/tail.go
index 7386e053d..942fd6bae 100644
--- a/plugins/inputs/tail/tail.go
+++ b/plugins/inputs/tail/tail.go
@@ -86,9 +86,10 @@ func (t *Tail) Start(acc telegraf.Accumulator) error {
 		for file, _ := range g.Match() {
 			tailer, err := tail.TailFile(file,
 				tail.Config{
-					ReOpen:   true,
-					Follow:   true,
-					Location: &seek,
+					ReOpen:    true,
+					Follow:    true,
+					Location:  &seek,
+					MustExist: true,
 				})
 			if err != nil {
 				errS += err.Error() + " "