TITLE
    Mac OS X Server: Changing Apache HostnameLookups Value
Article ID:
Created:
Modified: 		30964
4/23/99
4/26/99
TOPIC

    Changing the HostnameLookups value in Apache from the default of "no" can cause performance problems and make your server vulnerable to Denial of Service attacks.

DISCUSSION

    The Apache "HostnameLookups" property allows Apache enter the actual hostname (vs. just the IP address) address into its logs. You should NOT change it from the default value of "No." Enabling HostnameLookups can seriously degrade your servers' performance and increase your risk of DenialOfService attacks.

    Should it become necessary to resolve an IP address to a DNS name, the utility "logresolve" (located in the /usr/sbin directory) can be used to obtain this information.

    To use logresolve:

    1) Launch the logresolve utility
    2) Enter the IP address in question into the terminal window
    3) Press the return key
    4) The DNS name of that IP address displays in the terminal window

Document Information
Product Area: Mac OS System Software
Category: Mac OS X Server
Sub Category: Apple File Services

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