Installation guide

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Device Manager Guide, Cisco ACE 4700 Series Application Control Engine Appliance
OL-26645-02
Chapter 6 Configuring Real Servers and Server Farms
Configuring Health Monitoring
Table 6-9 Probe Types
Probe Type Description
DNS Sends a request to a DNS server giving it a configured domain. To determine
if the server is up, the ACE appliance must receive the configured IP address
for that domain.
ECHO-TCP Sends a string to the server and compares the response with the original
string. If the response string matches the original, the server is marked as
passed. If not, the ACE appliance retries as configured before the server is
marked as failed.
ECHO-UDP Sends a string to the server and compares the response with the original
string. If the response string matches the original, the server is marked as
passed. If not, the ACE appliance retries as configured before the server is
marked as failed.
FINGER Sends a probe to the server to verify that a defined username is a username
on the server.
FTP Initiates an FTP session. By default, this probe is for an anonymous login
with the option of configuring a user ID and password. The ACE appliance
performs an FTP GET or LS to determine the outcome of the problem. This
probe supports only active connections.
HTTP Sets up a TCP connection and issues an HTTP request. Any valid HTTP
response causes the probe to mark the real server as passed.
HTTPS Similar to an HTTP probe, but this probe uses SSL to generate encrypted
data.
Note This option is not available for the ACE NPE software version (see
the “Information About the ACE No Payload Encryption Software
Version” section on page 1-2).
ICMP Sends an ICMP request and listens for a response. If the server returns a
response, the ACE appliance marks the real server as passed. If there is no
response and times out, or an ICMP standard error occurs, such as
DESTINATION_UNREACHABLE, the ACE appliance marks the real
server as failed.
IMAP Initiates an IMAP session, using a configured user ID and password. Then,
the probe attempts to retrieve e-mail from the server and validates the result
of the probe based on the return codes received from the server.
POP Initiates a POP session, using a configured user ID and password. Then, the
probe attempts to retrieve e-mail from the server and validates the result of
the probe based on the return codes received from the server.
RADIUS Connects to a RADIUS server and logs into it to determine if the server is up.
RTSP Establishes a TCP connection and sends a request packet to the server. The
ACE compares the response with the configured response code to determine
whether the probe succeeded.
Scripted Executes probes from a configured script to perform health probing. This
method allows you to author specific scripts with features not present in
standard probes.