We help IT Professionals succeed at work.
Get Started

Having issues with old data, DNS/DHCP

Mark asked
Last Modified: 2015-10-13
I'm having a few issues with DNS/DHCP, I'll ask about these one at a time.

bind 9.9.7-P1, dhcpd 4.2.5-P1, Slackware 64, 14.1

First, old leases seem to hang around forever in /var/state/dhcp/dhcpd.leases, example below. Those listed are from back in March. None of the computers in the lease file are currently connected. Why are they hanging around?

Should static IPs be in there? If so, something is not working.

# The format of this file is documented in the dhcpd.leases(5) manual page.
# This lease file was written by isc-dhcp-4.2.5-P1

lease {
  starts 6 2015/03/07 11:46:52;
  ends 0 2015/03/08 11:46:52;
  tstp 0 2015/03/08 11:46:52;
  cltt 6 2015/03/07 11:46:52;
  binding state free;
  hardware ethernet 00:16:17:46:70:69;
  uid "\001\000\026\027Fpi";
lease {
  starts 2 2015/03/17 17:01:10;
  ends 3 2015/03/18 17:01:10;
  tstp 3 2015/03/18 17:01:10;
  cltt 2 2015/03/17 17:01:10;
  binding state free;
  hardware ethernet c8:9c:dc:6e:24:e8;
  uid "\001\310\234\334n$\350";

Open in new window

My dhcpd.conf file:


ddns-updates on;
update-static-leases on;
allow unknown-clients;  # default, deprecated (man dhcpd.conf)
ignore client-updates;  # see https://www.centos.org/forums/viewtopic.php?t=29256, man dhcpd.conf: ignore client-updates
ddns-update-style interim;
default-lease-time 86400;

log-facility local7;

zone hprs.local. { primary; }
zone 0.168.192.in-addr.arpa. { primary; }

subnet netmask {
    option routers;
    option domain-name-servers;
    option domain-name "hprs.local";
    ddns-domainname = "hprs.local.";
    ddns-rev-domainname = "in-addr.arpa.";

# Web Server (Linux)
host webserver {
    hardware ethernet 60:A4:4C:61:9C:FE;

# SQL Server Database Server (Server 2008)
host server {
#    hardware ethernet 40:E0:4C:39:7F:61;
    hardware ethernet 3C:1E:04:47:16:B0;

# Network Attached Storage (Linux)
host ohprsstorage {
    hardware ethernet F4:6D:04:60:04:38;

# COMMON workstation (WIN7)
host COMMON {
    hardware ethernet 2C:27:D7:2F:CF:7A;

host ricoh {
    hardware ethernet 00:26:73:55:63:AB;

# Postage meter
host postage {
    hardware ethernet 00:10:60:B6:72:D4;

Open in new window

Watch Question
President, IT4SOHO, LLC
This problem has been solved!
Unlock 1 Answer and 3 Comments.
See Answer
Why Experts Exchange?

Experts Exchange always has the answer, or at the least points me in the correct direction! It is like having another employee that is extremely experienced.

Jim Murphy
Programmer at Smart IT Solutions

When asked, what has been your best career decision?

Deciding to stick with EE.

Mohamed Asif
Technical Department Head

Being involved with EE helped me to grow personally and professionally.

Carl Webster
CTP, Sr Infrastructure Consultant
Ask ANY Question

Connect with Certified Experts to gain insight and support on specific technology challenges including:

  • Troubleshooting
  • Research
  • Professional Opinions
Did You Know?

We've partnered with two important charities to provide clean water and computer science education to those who need it most. READ MORE