Understanding ACL Priority, Tcp/Udp | Juniper Networks EX2500

Chapter 5: Quality of Service

Table 13: Well-Known Application Ports

	TCP/UDP		TCP/UDP		TCP/UDP
Number	Application	Number	Application	Number	Application

20	ftp-data	79	finger	179	bgp
21	ftp	80	http	194	irc
22	ssh	109	pop2	220	imap3
23	telnet	110	pop3	389	ldap
25	smtp	111	sunrpc	443	https
37	time	119	nntp	520	rip
42	name	123	ntp	554	rtsp
43	whois	143	imap	1645, 1812	RADIUS
53	domain	144	news	1813	RADIUS accounting
69	tftp	161	snmp	1985	hsrp
70	gopher	162	snmptrap

Understanding ACL Priority

Each ACL has a unique priority value, based on its number. The lower the ACL number, the higher the priority, so ACL 1 has the highest priority.

The priority value is used to decide which ACL rule to apply when a packet matches one or more ACLs. When an incoming packet matches the highest priority ACL, the ACL’s configured action takes place. The other assigned ACLs are considered in numeric order, from lowest to highest.

In the following example, the switch considers ACL 128 before ACL 130 because ACL 128 has a higher priority. The order in which the ACLs are assigned to a port does not affect their priority.

Port 1 access group

ACL IP Extended 128:

TCP

Port number = 80

Action = permit

ACL IP Extended 129:

TCP

Port number = 23

Action = deny

ACL IP Extended 130:

TCP

Port number = less than 100

Action = permit

Using ACL Filters 55

Image 69

Juniper Networks EX2500 manual Understanding ACL Priority, Tcp/Udp

Contents

North Mathilda Avenue Sunnyvale, CA Configuration Guide Ii „ Table of Contents Chapter VLANs Rmon Overview Rmon Group 1-Statistics Rmon Group 2-History Chapter Ports and Trunking Port Mirroring Overview Configuring Port Mirroring AppendixesIndexes Port-Based Vlan Assignment Default Vlan SettingsPage List of Tables EX2500 Ethernet Switch Configuration Guide „ List of Tables Objectives About This GuideAudience Supported Platforms Icon Meaning Description Documentation Conventions List of Technical Publications Documentation FeedbackRequesting Technical Support Opening a Case with Jtac Self-Help Online Tools and Resources EX2500 Ethernet Switch Applications Page Configuring the Management Interface Accessing the Switch Configure the default gateway. Enable the gateway Dynamic Host Configuration Protocol Using the EX2500 Web Device Manager Using Telnet Configuring EX2500 Web Device Manager Access via Https Configuring EX2500 Web Device Manager Access via Http SNMPv1, SNMPv2 Using Snmp Default Configuration User ConfigurationSNMPv3 SNMPv1 Trap Host Configuration Configuring Snmp Trap HostsSNMPv2 Trap Host Configuration Configure an entry in the notify table SNMPv3 Trap Host Configuration Securing Access to the Switch How Radius Authentication Works Radius Authentication and AuthorizationConfiguring Radius on the Switch Configure the Radius secret Radius Authentication Features in the EX2500 Switch Radius Attributes for EX2500 User Privileges Switch User Accounts TACACS+ Authentication How TACACS+ Authentication WorksTACACS+ Authentication Features in the EX2500 Switch „ starttime „ stoptime „ elapsedtime „ disccause Command Authorization and Logging Configuring TACACS+ Authentication on the SwitchConfigure the TACACS+ secret and second secret Generating RSA Host and Server Keys for SSH Access Configuring SSH Features on the SwitchSecure Shell SSH Encryption of Management Messages SSH Integration with Radius and TACACS+ Authentication End User Access Control User Access Control Considerations for Configuring End User Accounts Logging In to an End User Account Listing Current Users Vlan Overview VLANs VLANs and Port Vlan ID Numbers „ Port configurationVlan Numbers Pvid Numbers Vlan Tagging Illustrates the default Vlan settings on the switch Default Vlan Settings Port-Based Vlan Assignment Vlan Topologies and Design Considerations Vlan Configuration Rules Multiple VLANs example in is described in Table Multiple VLANs Configuration Example Enable tagging on uplink ports that support multiple VLANs Private Vlan Ports Private VLANs Private Vlan Configuration Example Private Vlan Configuration GuidelinesConfigure a secondary Vlan and map it to the primary Vlan Verify the configuration Spanning Tree Overview Spanning Tree Protocol Bridge Protocol Data Units BPDUs Determining the Path for Forwarding BPDUsBridge Priority Changing the Spanning Tree Mode Spanning Tree Group Configuration GuidelinesPort Priority Port Path Cost Creating a Vlan Rules for Vlan Tagged PortsAdding and Removing Ports from STGs Port State Changes Rapid Spanning Tree Protocol Rstp Configuration Example Rstp Configuration GuidelinesPort Type and Link Type Edge Port Default Spanning Tree Configuration Why Do We Need Multiple Spanning Trees?Per Vlan Rapid Spanning Tree Configuring Pvrst Pvrst Configuration Guidelines Multiple Spanning Tree Protocol Mstp Configuration GuidelinesMstp Region Common Internal Spanning Tree Implementing Multiple Spanning Tree Groups Multiple Spanning Tree Groups Configuration Example Vlan Fast Uplink Convergence Configuring Fast Uplink Convergence Configuration Guidelines Ports and Trunking Trunking OverviewStatistical Load Distribution Built-In Fault Tolerance Before Configuring Static TrunksTrunk Group Configuration Rules Port Trunk Group Configuration Example Port Trunking Configuration Example Follow these steps on the EX2500 switch Define a trunk group Link Aggregation Control Protocol Configurable Trunk Hash Algorithm„ Destination MAC Dmac „ Destination IP DIP 48 „ Link Aggregation Control Protocol Configuring Lacp Lacp Configuration GuidelinesOptionally Reducing Lacp Timeout Set the Lacp mode Ex2500config-if# lacp timeout short ex2500config-if# exit QoS Overview Quality of Service COS Using ACL Filters IP Standard ACLs MAC Extended ACLsTo delete a MAC Extended ACL To delete an IP Standard ACL To delete an IP Extended ACL IP Extended ACLs TCP/UDP Understanding ACL Priority Assigning ACLs to a Port ACL Configuration ExamplesViewing ACL Statistics ACL Example 1-Blocking Traffic to a Host Add the ACL to a port ACL Example 3-Blocking Http Traffic Assign the ACLs to a port ACL Example 4-Blocking All Except Certain Packets Using Storm Control Filters Configuring Storm ControlBroadcast Storms Differentiated Services Concepts Using Dscp Values to Provide QoS Assured Forwarding Drop Precedence Class Per Hop Behavior Use the following command to perform Dscp mapping QoS LevelsDscp Mapping Shows the priority bits in a VLAN-tagged packet Using 802.1p Priority to Provide QoS Queuing and Scheduling Rmon Overview Remote Monitoring Rmon Group 1-Statistics Configure the Rmon statistics on a port Configure the Rmon History parameters for a port Configuring Rmon HistoryThis configuration enables Rmon History collection on port Rmon Group 2-History Alarm MIB Objects Rmon Group 3-AlarmsConfiguring Rmon Alarms Configure the Rmon Alarm parameters to track Icmp messages Rmon Group 9-Events Ex2500config# rmon event 110 type log-onlyPage Igmp Snooping Igmp FastLeave IGMPv3 Snooping Igmp Snooping Configuration Example Ex2500# show ip igmp groups Static Multicast Router High Availability Overview High Availability Through Uplink Failure Detection Failure Detection Pair Spanning Tree Protocol with UFD UFD Configuration Guidelines Monitoring UFD UFD Configuration ExamplePage Appendixes EX2500 Ethernet Switch Configuration Guide 80 „ Appendixes Port Mirroring Overview „ Port Mirroring Overview on „ Configuring Port Mirroring on Configuring Port Mirroring „ Index on Indexes EX2500 Ethernet Switch Configuration Guide 84 „ Indexes Numerics Index Multi-links between switches, port trunking Management interface, configuringPhysical. See switch ports Internet Group Management Protocol. See Igmp QoS Quality of Service. See QoSSecurity Segmentation. See IP subnets Segments. See IP subnets Example showing multiple VLANs Virtual Local Area Networks. See VLANs