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Manual Chapter: BIG-IP v9.0 New and Updated Commands: Managing Local Application Traffic
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4

Managing Local Application Traffic


Introducing local application traffic configuration

There are many tasks that you can perform to customize the way that the BIG-IP system manages local network traffic. The primary command-line tool that you use to perform these tasks is the bigpipe utility. When managing SSL traffic, however, there are other tools you can use in addition to the bigpipe utility.

Local traffic management tools

The command-line tools that you can use to manage local traffic passing through the BIG-IP system are:

  • The bigpipe utility
  • The OpenSSL toolkit

The bigpipe utility is the primary command-line tool that you can use to manage local traffic. Table 4.1 lists and briefly describes the bigpipe commands related to local traffic management For more details on these commands, see the online man pages..

Table 4.1 bigpipe commands for managing local network traffic 
Command Description
help
Displays online help for an individual bigpipe command.
auth
Creates the specified type of authentication configuration object. This command is new in version 9 systems and removes the need for the former bigpipe authz command.
class
Creates a class and displays all classes included with BIG-IP system.
conn
Shows information about current connections such as the source IP address, virtual server and port, and node.
db
Allows you to configure certain settings globally.
monitor
Defines a health check monitor.
nat
Defines external network address translations for nodes.
node
Defines node property settings.
ocsp responder
Creates or modifies an OCSP responder object, required for SSL OCSP remote authentication. This command is new in version 9 systems.
pool
Defines load balancing pools.
profile
Creates or modifies any type of profile that you specify. This command is new in version 9 systems and removes the need for the former bigpipe proxy command.
radius server
Creates or modifies a RADIUS server object, required for RADIUS remote authentication. This command is new in version 9 systems.
rule
Defines load balancing rules.
service
Defines properties for services.
snat
Defines and sets options for SNAT (Secure NAT).
snatpool
Defines and sets options for SNAT pools. This command is new in version 9 systems.
virtual
Defines virtual servers, virtual server mappings, and virtual server properties.

 

Performing local traffic management tasks

Using the tools listed in the previous section, you can perform a number of local traffic management tasks. Table 4.2 lists those tasks that you can perform using the bigpipe utility.

For many of these tasks, you use multiple bigpipe commands in combination. In cases where the commands you use to perform a task differ from those that you used in pre-9.0 versions of the BIG-IP system, this section contains revised procedures, following table 4.2 .

Important

The command syntax shown in Table 4.2 is not exhaustive. For each command, see the corresponding man page for the correct syntax.
Table 4.2 Local traffic management tasks 
Tasks to configure local traffic management
Command or utility to use
Create and configure a virtual server.
bigpipe virtual
Create and configure a node.
bigpipe node
Create and configure a load balancing pool.
bigpipe pool, bigpipe virtual pool
Monitor the health of a pool member.
bigpipe monitor, bigpipe pool
Monitor the performance of a pool member using the dynamic ratio load balancing method.
bigpipe monitor, bigpipe pool, third-party plug-ins
Manage HTTP traffic.
bigpipe profile http, bigpipe virtual profile
Manage Fast HTTP traffic.
bigpipe profile fasthttp, bigpipe virtual profile
Manage FTP traffic.
bigpipe profile ftp, bigpipe virtual profile
Manage layer 4 traffic.
bigpipe profile layer4, bigpipe virtual profile
Manage TCP traffic.
bigpipe profile tcp, bigpipe virtual profile
Manage UDP traffic.
bigpipe profile udp, bigpipe virtual profile
Configure connection pooling.
bigpipe profile oneconnect, bigpipe virtual profile
Manage Real-time Streaming Protocol (RTSP) traffic.
bigpipe profile stream, bigpipe virtual profile
Implement session persistence (excluding terminated SSL sessions).
bigpipe profile persist, bigpipe virtual persist
Implement persistence for terminated SSL sessions.
bigpipe rule
Enable Keep-Alive support for HTTP/1.0 requests.
bigpipe profile
Configure compression for HTTP server responses.
bigpipe profile
Configure authentication using a remote LDAP server.
bigpipe profile, bigpipe auth
Configure authentication using a remote RADIUS server.
bigpipe profile, bigpipe auth, bigpipe radius server
Configure authentication using a remote TACACS+ server.
bigpipe profile, bigpipe auth
Configure certificate-based authorization using a remote LDAP server.
bigpipe profile, bigpipe auth
Configure authentication using a remote SSL OCSP responder.
bigpipe profile, bigpipe auth, bigpipe ocsp responder
Implement secure network address translations (SNATs).
bigpipe snat, bigpipe snat translation, bigpipe snatpool, bigpipe rule (optional)
Implement rate shaping to customize throughput.
bigpipe rate class, bigpipe packet filter rule, bigpipe virtual, bigpipe rule (optional)
Create a class for use within an iRule.
bigpipe class
Customize the management of individual connections.
bigpipe rule
Display statistical information for a virtual server or virtual address.
bigpipe virtual <ip_address>:[<service>] show
Display statistical information for a service.
bigpipe <service_name>
Display statistical information for a node.
bigpipe node <ip_address> show
Display statistical information for a SNAT.
bigpipe snat <snat_address> show
Enable or disable a virtual server.
bigpipe virtual <name> enable | disable
Enable or disable a virtual address.
bigpipe virtual <name> enable | disable
Enable or disable a node.
bigpipe node <ip_address>:<sercice> enable | disable

 

The following sections describe some of the local traffic management tasks that you can perform on the BIG-IP system.

Setting up a basic load balancing configuration

Once you have configured your base network, you can easily set up a basic, local traffic management system by implementing a profile, a load balancing pool, and a virtual server.

To set up a basic load balancing configuration

  1. Decide what types of traffic you want the BIG-IP system to manage, as well as whether you want to implement session persistence, connection persistence, and remote authentication.
  2. For each decision in step 1, decide whether you want to use the corresponding default profile that the BIG-IP system provides, or whether you want to create a custom profile.
  3. If you want to create custom profiles, use the bigpipe profile command, specifying the appropriate type of profile as an argument to the bigpipe profile command.
    If you do not want to create custom profiles, skip this step.
  4. Create one or more load balancing pools, using the bigpipe pool command.
  5. Create a virtual server, using the bigpipe virtual command, and assign to it any profiles and pools that you created. If you are using default profiles, some of those profiles might already be assigned to the virtual server by default.

Managing traffic types

To manage a particular type of network traffic, such as HTTP traffic, you can either create a custom profile of that type (recommended) or modify the default, system-supplied profile of that type (not recommended). After creating or modifying the profile, you then assign the profile to a virtual server. You can manage these types of traffic:

  • HTTP
  • FTP
  • Layer 4
  • TCP
  • UDP
  • Client SSL
  • Server SSL

You can also enable session persistence and connection persistence, as well as authenticate network traffic using various types of remote authentication servers. For more information, see the following sections:

For more information on profiles, see the profile man page, as well as the man page for each profile type.

To manage a specific type of network traffic

  1. Create a profile for a specific type of traffic, such as SSL, using the bigpipe profile command. For example, you can manage client-side SSL traffic by using the command bigpipe profile clientssl and specifying its arguments.
  2. Assign the profile to a virtual server, using the bigpipe virtual command.

Optionally, you can write an iRule that includes various commands, which dynamically modify profile settings. For more information, see the Configuration Guide for Local Traffic Management.

Setting Link QoS and IP ToS levels on packets

You can use the bigpipe utility to set Quality of Service (QoS) and Type of Service (ToS) levels on packets. You can do this not only for all traffic targeted to a load balancing pool, but also for specific types of traffic, such as layer 4, TCP, and UDP traffic.

To set QoS and ToS levels

  1. Decide whether you want to set QoS and ToS levels for traffic targeted for an entire pool or for specific types of traffic, or both.
    1. If you want to set the QoS and ToS levels for an entire pool, use the bigpipe pool command with one or more of the following arguments: link qos to client, link qos to server, ip tos to client, and ip tos to server.
    2. If you want to set the QoS and ToS levels for certain types of traffic, use the bigpipe profile command to create or modify a Fast L4, TCP, or UDP profile.
  2. Verify that the pool or the profile that you created or modified is assigned to a virtual server. To do this, use the following syntax:

    bigpipe virtual <name> list

Setting idle timeout values

You can use the bigpipe utility to set timeout values for layer 4, HTTP, TCP, or UDP connections that remain idle. You do this by creating or modifying a Fast L4, Fast HTTP, TCP, or UDP profile.

To set idle timeout values

  1. Create or modify a Fast L4, Fast HTTP, TCP, or UDP profile, using the bigpipe profile command.
  2. Specify the idle timeout argument to set a timeout value.
  3. Verify that the profile you created or modified is assigned to a virtual server.

Generating SSL certificates

When you want the BIG-IP system to manage SSL traffic (that is, authenticate, decrypt, and encrypt SSL traffic), you must generate SSL certificates that the BIG-IP system can use as part of the authentication process.

To generate SSL certificates from the command line, you can use the industry-standard OpenSSL toolkit. You can generate Certificate Authority (CA) certificates, client certificates, certificates for web sites, and CRLs. You can also perform a number of other certificate-related tasks.

Generating CA certificates

You can use the OpenSSL toolkit to generate CA certificates that are trusted for client authentication.

To generate a CA certificate

  1. Create a key for the CA, using the openssl command.
    For example:

    openssl genrsa -rand .rand -out bigmirror-ca.key 1024
  2. Create a request for a certificate, using the key that you created in step 1.
    For example:

    openssl req -x509 -new -key bigmirror-ca.key -out
    bigmirror-ca.crt
  3. Create a configuration file that causes a CRL distribution point to use LDAP.
    For example, this command sequence creates a configuration file named bigmirror-ca.ext:

    echo -e '[ v3_ca ]\nsubjectKeyIdentifier=hash\nauthorityKeyIdentifier=keyi
    d:always,issuer:always\nbasicConstraints = CA:true\n[
    crl_ext ]\ncrlDistributionPoints=@crldp\n[ crldp
    ]\nURI=ldap://192.168.33.100:389/dc=bigmirror,dc=com?cert
    ificateRevocationList;binary?sub?cn=DistPoint1' >
    bigmirror-ca.ext
  4. Generate a CA certificate that is trusted for client authentication, using the previously generated key and certificate.
    1. If you want to generate the CA certificate with the LDAP CRL distribution point, use the openssl x509 command, as in the following example:

      openssl x509 -in bigmirror-ca.crt -out
      bigmirror-ca.trusted.crt -signkey
      bigmirror-ca.key -days 300 -addtrust clientAuth
      -addtrust serverAuth -setalias "Bigmirror CA" -extensions v3_ca -extensions
      crl_ext -extfile bigmirror-ca.ext
    2. If you want to generate the CA certificate without the LDAP CRL distribution point, use the openssl x509 command, as in the following example:

      openssl x509 -in bigmirror-ca.crt -out
      bigmirror-ca.trusted.crt -signkey
      bigmirror-ca.key -days 300 -addtrust clientAuth -addtrust serverAuth
      -setalias "Bigmirror CA" -extensions v3_ca
  5. Generate a non-trusted (default) CA certificate.
    For example:

    openssl x509 -in bigmirror-ca.trusted.crt -clrtrust -out bigmirror-ca.crt
  6. Convert the certificate to DER format for browsers (import this into browsers).
    For example:

    openssl x509 -inform pem -outform der -in bigmirror-ca.crt -out bigmirror-ca.der

Creating client certificates

For client-side authentication between a client and a BIG-IP system, you can create a certificate for that client.

To create a client certificate

  1. Generate a client key.
    For example:

    openssl genrsa -rand .rand -out auser1.key 1024
  2. Generate a client certificate request, using the previously-generated key.
    For example:

    openssl req -new -out auser1.req -key auser1.key
  3. Generate a client certificate.
    In the following example, the certificate is named auser1.crt.
    1. If you want to generate the client certificate with the LDAP CRL distribution point, use the openssl x509 command, as in the following example:

      openssl x509 -req -in auser1.req -out auser1.crt
      -CAkey bigmirror-ca.key -CA bigmirror-ca.crt -days 300
      -CAcreateserial -CAserial serial -extensions crl_ext
      -extfile bigmirror-ca.ext
    2. If you want to generate the client certificate without the LDAP CRL distribution point, use the openssl x509 command, as in the following example:

      openssl x509 -req -in auser1.req -out auser1.crt
      -CAkey bigmirror-ca.key -CA bigmirror-ca.crt -days 300
      -CAcreateserial -CAserial serial
  4. Create a PKCS12 file using the above key and certificate pairs.
    For example:

    openssl pkcs12 -export -in auser1.crt -inkey auser1.key
    out auser1.p12 -name "auser1 pkcs12"

Creating a certificate for a web site

For server-side authentication between a web site and a BIG-IP system, you can create a certificate for that web site.

To create a certificate for a web site

  1. Create a key. For example:

    openssl genrsa -rand .rand -out www.test.net.key 1024
  2. Generate a certificate request using the key that you generated in step 1. For example: openssl req -new -key www.test.net.key -out
    www.test.net.req
  3. Using the request that you generated in step 2, generate a certificate named for the web site.
    1. If you want to generate the certificate with the LDAP CRL distribution point, use the openssl x509 command, as in the following example:

      openssl x509 -req -in www.test.net.req -out
      www.test.net.crt -CAkey bigmirror-ca.key -CA
      bigmirror-ca.crt -days 300 -CAcreateserial
      -CAserial serial -extensions crl_ext -extfile bigmirror-ca.ext
    2. If you want to generate the certificate without the LDAP CRL distribution point, use the openssl x509 command, as in the following example:

      openssl x509 -req -in www.test.net.req -out
      www.test.net.crt -CAkey bigmirror-ca.key -CA
      bigmirror-ca.crt -days 300 -CAcreateserial -CAserial
      serial

Working with certificate revocation

You can use the OpenSSL toolkit to create a certificate revocation list (CRL). The BIG-IP system checks a CRL to see if a client or server certificate being presented for authentication has been revoked.

You can also use the toolkit to revoke a certificate.

To create a certificate revocation list

  1. Create a configuration file for the serial or index option.
    For example:

    echo -e
    'default_ca=ca\n[ca]\ndatabase=index.txt\nserial=serial' >
    bigmirror-ca.config
  2. Generate a CRL that expires in thirty days. For example:

    openssl ca -config bigmirror-ca.config -gencrl -crldays
    30 -keyfile bigmirror-ca.key -cert bigmirror-ca.crt -out
    bigmirror-ca.crl

To revoke a certificate

Revoke a client certificate, using the openssl command. For example, to revoke the client certificate auser1.crt:

ropenssl ca -config bigmirror-ca.config -keyfile
bigmirror-ca.key -cert bigmirror-ca.crt -revoke auser1.crt

Associating keys and certificates with SSL profiles

You can associate a key and a certificate with an SSL profile by using the bigpipe profile command and specifying the key and certificate file names as arguments. For more information, see the man page for the profile command.

Performing other certificate-related tasks

There are a number of other SSL-certificate-related tasks that you can perform, using the openssl utility.

To verify a certificate

Use this command to verify a certificate:

openssl verify -CAfile bigmirror-ca.crt www.test.net.crt

To view a CRL

Use this command to view a CRL:

openssl crl -in bigmirror-ca.crl -text -noout

To view certificate information

Use this command to view certificate information:

openssl x509 -in www.test.net.crt -text -noout

To convert a certificate to PEM format

Use this command to convert a certificate from PKCS12 (.P12 or.PFX) format to PEM format:

openssl pkcs12 -in auser1.p12 -out auser1.pem

To add a password to an RSA key

Use this command to add a password to an RSA key:

openssl rsa -in auser1.key -out auser1-enc.key -des3 -passout pass:secret

To strip a password from an RSA key

Use this command to strip a password from an RSA key:

openssl rsa -in auser1-enc.key -out auser1.key -passin pass:secret

Configuring remote server authentication

When you want to configure the BIG-IP system to use a remote server for authenticating application traffic, you use the bigpipe auth, bigpipe profile, and bigpipe virtual commands. The types of authentication servers that you can use to authenticate network traffic are:

  • LDAP servers
  • RADIUS servers
  • TACACS+ servers
  • SSL Client Certificate LDAP servers
  • SSL OCSP responders

If the remote authentication server is an SSL OCSP responder or a RADIUS server, you also use the bigpipe ocsp responder or bigpipe radius server command.

To configure the BIG-IP system for remote authentication

  1. Create an authentication configuration object of the appropriate type, using the bigpipe auth command.
  2. Create an authentication profile of the same type as the configuration object, using the bigpipe profile command and specifying the configuration object name as one of the profile settings.
  3. If the remote authentication server is an SSL OCSP responder or a RADIUS server, create the appropriate object.
    1. For an SSL OCSP responder, create an SSL OCSP responder object, using the bigpipe ocsp responder command.
    2. For a RADIUS server, create a RADIUS server object, using the bigpipe radius server command.
  4. Associate the authentication profile with a virtual server, using the bigpipe virtual command.

Associating health monitors with pools and nodes

To associate a health monitor with a pool or a node, you must create a monitor, create a pool or node, and then associate the monitor with the pool.

To associate a health monitor with a load balancing pool

  1. Create a monitor, using the bigpipe monitor command, for monitoring the health of the servers that make up your load balancing pool.
  2. Configure a load balancing pool with the bigpipe pool monitor or bigpipe pool monitor all command, specifying the name of the health monitor that you want to use to monitor the pool members. Using these commands, you can assign the same monitor to all pool members, or you can assign different health monitors to individual pool members.
  3. Assign the pool to a virtual server, using the bigpipe virtual pool command.

To associate a health monitor with a node

  1. Create a monitor, using the bigpipe monitor command, for monitoring the health of a node.
  2. Configure a node with the bigpipe node monitor command, specifying the name of the monitor that you want to use to monitor the node.

Configuring HTTP compression

To configure the BIG-IP system to compress HTTP server responses, you use the bigpipe profile and bigpipe virtual commands.

To configure HTTP compression

  1. Configure the compression-related settings of an HTTP profile, using the bigpipe profile http command.
  2. Assign the HTTP profile to a virtual server, using the bigpipe virtual command.

Redirecting HTTP requests

You can redirect HTTP requests by configuring an HTTP profile and specifying a fallback host within the profile.

To redirect HTTP requests

  1. Using the bigpipe profile http command, create or modify an HTTP profile, specifying a value for the fallback argument. You can specify either a URI or the default fallback host, or you can specify that you want no HTTP redirection.
  2. Verify that the HTTP profile you created or modified is assigned to a virtual server.

Rewriting HTTP redirections

You can rewrite HTTP redirections by configuring an HTTP profile and specifying that you want the BIG-IP system to rewrite certain HTTP redirections.

To rewrite HTTP redirections

  1. Using the bigpipe profile http command, create or modify an HTTP profile, specifying a value for the redirect rewrite argument.
  2. Verify that the HTTP profile you created or modified is assigned to a virtual server.

Inserting and erasing HTTP headers

You can insert headers into HTTP requests or remove headers from HTTP requests by configuring an HTTP or Fast HTTP profile.

To insert or erase HTTP headers

  1. Using the bigpipe profile http command, create or modify an HTTP profile, specifying a value for either the header insert, header erase, or insert xforwarded for attributes.
  2. Verify that the HTTP or Fast HTTP profile you created or modified is assigned to a virtual server.

Tip


You can also manipulate HTTP headers by configuring a Fast HTTP profile, using the bigpipe profile fasthttp command.

Configuring clone pools

Clone pools are designed for intrusion detection. You can implement clone pools by configuring a virtual server. A clone pool receives all of the same traffic as the normal pool. You therefore use clone pools to copy traffic to intrusion detection systems.

To configure a clone pool

Using the bigpipe virtual command, create or modify a virtual server, specifying a value for the clone pool argument.

Implementing session persistence

To implement session persistence for connections passing through a virtual server, you use the bigpipe profile and bigpipe virtual commands. You can implement these types of session persistence:

  • Cookie
  • Destination Address Affinity
  • Microsoft Remote Desktop Protocol (MSRDP)
  • Session Initiation Protocol (SIP)
  • Source Address Affinity
  • SSL
  • Universal

To configure session persistence

  1. Create a persistence profile, using the bigpipe profile command, that corresponds to the type of persistence you want to implement.
  2. Assign the persistence profile to a virtual server, using the bigpipe virtual persist and bigpipe virtual fallback persist commands.

Implementing connection persistence

To implement connection persistence, you can add Keep-Alive headers into HTTP /1.0 headers where none exist. (By default, HTTP/1.1 connections include Keep-Alive support.) You can also enable a feature known as connection pooling, which keeps server-side connections open for re-use by other client requests. You enable Keep-Alive support and connection pooling by creating or modifying an HTTP or Fast HTTP profile, as well as a OneConnect profile.

To add Keep-Alive headers into HTTP requests

  1. To ensure that HTTP connections stay open, use the bigpipe profile http command and specify the oneconnect transformations argument. This ensures that the BIG-IP system inserts a Connection:Keep-Alive header into any HTTP /1.0 request that does not already contain one.
  2. Make sure that you have assigned the HTTP or Fast HTTP profile to a virtual server, using the bigpipe virtual command.

To enable connection pooling

  1. Using the bigpipe profile oneconnect command, configure a profile for connection pooling.
  2. Assign the profile to a virtual server, using the bigpipe virtual profile command.

Tip


You can also configure connection persistence settings by configuring a Fast HTTP profile, using the bigpipe profile fasthttp command.

Unchunking and rechunking HTTP response data

If you want to unchunk a chunked HTTP response for the purpose of inspecting the content, you can enable unchunking by configuring an HTTP profile.

To configure HTTP response chunking

  1. Using the bigpipe profile http command, create or modify an HTTP profile and specify the response argument.
  2. Make sure that you have assigned the HTTP profile to a virtual server, using the bigpipe virtual command.

Implementing SNATs

There are two basic ways to create a SNAT. You can either directly assign a translation address to one or more original IP addresses, or you can create a SNAT pool and then assign the SNAT pool to the original IP addresses. In the latter case, the BIG-IP system automatically selects a translation address from the assigned SNAT pool.

Note that you can assign these types of mappings from within an iRule.

Mapping a single translation address to an original address

  1. Designate an IP address as a translation address, using the bigpipe snat translation command.
  2. Map the translation address to one or more original IP addresses, using the bigpipe snat command or the bigpipe rule command.

Mapping a SNAT pool to an original address

  1. Create a pool of translation addresses (that is, SNAT pool), using the bigpipe snatpool command.
  2. Map the SNAT pool to one or more original IP addresses, using either the bigpipe snat command or the bigpipe rule command.

Configuring a last hop pool

By default, the auto last hop feature is enabled on the BIG-IP system. If you want to disable that feature and instead explicitly define a last hop router, you can create a last hop pool and assign it to a virtual server.

To configure a last hop pool

  1. Using the bigpipe pool command, create a last hop pool that contains the router inside addresses.
  2. Assign the last hop pool to a virtual server, using the bigpipe virtual lasthop pool command.
  3. If you have not assigned an SSL profile to the virtual server, assign the profile to the virtual server, using the bigpipe virtual profile command.

Implementing rate shaping

To implement rate shaping, you must create a rate class, and then assign the rate class to a virtual server or a packet filter rule.

To implement rate shaping

  1. Create one or more rate classes, using the bigpipe rate class command.
  2. Assign the rate classes to a virtual server or a packet filter rule, using either the bigpipe virtual command or the bigpipe packet filter command.

Implementing iRules

To implement an iRule from the command line, you use the following procedure.

To implement an iRule

  1. Write a script using the industry-standard Tools Command Language (Tcl) and the commands that the BIG-IP system provides as Tcl extensions. Do not attempt to use any Tcl commands that the BIG-IP system has disabled. BIG-IP system extensions to Tcl, as well as disabled Tcl commands, are listed in the Configuration Guide for Local Traffic Management.
  2. Create an iRule by using the bigpipe rule command and giving the name of the Tcl script as an argument.
  3. Assign the iRule to a virtual server, using the bigpipe virtual rule command as shown in Table 4.3 .
Table 4.3 bigpipe syntax for assigning iRules to virtual servers
Task
Required Syntax
Associate an existing iRule with all existing virtual servers. In this case, the iRule becomes the only iRule associated with each virtual server. Because this command overwrites all previous iRule assignments, use of this command is not recommended.
b virtual all rule <iRule_name>
Associate multiple iRules iwth a virtual server
b virtual <virtual_server_name> rule <iRule1_name> <iRule2_name> ...
Remove the assignment of an iRule from a virtual server
b virtual <virtual_server_name> rule none
Remove the iRule assignments from all virtual servers
b virtual all rule none



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