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DNS lookup causes connection failure in Smart Protection Server of Deep Security

    • Updated:
    • 14 Sep 2015
    • Product/Version:
    • Deep Security 9.5
    • Deep Security 9.6
    • Platform:
    • Amazon AMI 32-bit
    • Amazon AMI 64-bit
    • CentOS 5.4 32-bit
    • CentOS 5.4 64-bit
    • CentOS 5.5 32-bit
    • CentOS 5.5 64-bit
    • CentOS 5.6 32-bit
    • CentOS 5.6 64-bit
    • CentOS 5.7 32-bit
    • CentOS 5.7 64-bit
    • CentOS 5.8 32-bit
    • CentOS 5.8 64-bit
    • CentOS 6 32-bit
    • CentOS 6 64-bit
    • CentOS 6.1 32-bit
    • CentOS 6.1 64-bit
    • CentOS 6.2 32-bit
    • CentOS 6.2 64-bit
    • HPUX 11.x
    • IBM AIX 6.1
    • Linux - Red Hat RHEL 5 32-bit
    • Linux - Red Hat RHEL 5 64-bit
    • Linux - Red Hat RHEL 6 32-bit
    • Linux - Red Hat RHEL 6 64-bit
    • Linux - SuSE 10
    • Linux - SuSE 10 64-bit
    • Linux - SuSE 11
    • Linux - SuSE 11 64-bit
    • Oracle Linux 5 32-bit
    • Oracle Linux 5 64-bit
    • Oracle Linux 6 32-bit
    • Oracle Linux 6 64-bit
    • Oracle Solaris 11 SPARC
    • Oracle Solaris 11 x86
    • Ubuntu 10.04 64-bit
    • Ubuntu 12.04 64-bit
    • Unix - Solaris (Sun) version 10 (SunOS 5.10)
    • Unix - Solaris (Sun) version 9 (SunOS 5.9)
Summary
In some Linux distributions protected by Deep Security Agent, the DNS query is very slow. This affects the Web Reputation Service (WRS) function and Anti-Malware function if the Smart Protection mode is enabled.
Details
Public
By default, glibc simultaneously performs IPv4 and IPv6 lookups starting on version 2.9. Some appliance DNS servers cannot properly handle these queries and make request time out. For more details, refer to the Linux Programmer's Manual.
To resolve the issue, do one of the following:
  • For Linux host using static IP, add "options single-request" in /etc/resolv.conf.
    options single-request
  • For Linux host using DHCP, add "RES_OPTIONS=single-request" in /etc/sysconfig/network (RHEL-like platforms).
    RES_OPTIONS=single-request
Premium
Internal
Rating:
Category:
Troubleshoot
Solution Id:
1104701
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