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| Note |
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This documentation is for troubleshooting DHCP with the omapi protocol |
Check messages log file on DHCP Server
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Check the messages file for evidence that DHCP is functioning
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# tail /var/log/messages May 5 08:53:32 abiquoserver dhcpd: DHCPREQUEST for 192.168.1.2 from 01:50:51:38:b1:ed via eth0.1 May 5 08:53:32 abiquoserver dhcpd: DHCPACK on 192.168.1.2 to 01:50:51:38:b1:ed via eth0.1 May 5 08:53:38 abiquoserver dhcpd: DHCPREQUEST for 192.168.0.2 from 01:16:31:ee:73:14 via eth0.2 May 5 08:53:38 abiquoserver dhcpd: DHCPACK on 192.168.0.2 to 01:16:31:ee:73:14 via eth0.2 |
DHCPREQUESTs should be followed by DHCPACKs log entries. If not, try restarting the DHCP service:
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Restart the DHCPD service
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service dhcpd restart |
Checking the DHCP relay server
Check the VLAN interfaces
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DHCP relay server creation scripts and configuration files
No. of DHCP | Name of generator script | Names of scripts generated by initial script | Other config files | Wiki link |
|---|---|---|---|---|
One | abiquo-relay-scripts.py | relay-config | dhcpd.conf | Manually Configuring One DHCP Relay Server |
Multiple | dhcpconf | config-routes-server.sh; and | dhcpd.conf | Manually configuring multiple DHCP relay servers |
Checking the DHCP server
Check the DHCP configuration file
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$ cat /etc/dhcpd.conf |
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dhcpd.conf
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ddns-update-style interim;
option classless-static-routes code 121 = array of integer 8;
option ms-classless-static-routes code 249 = array of integer 8;
omapi-port 7911;
subnet 0.0.0.0 netmask 0.0.0.0 {
default-lease-time 60000;
max-lease-time 720000;
option subnet-mask 255.255.255.0;
option domain-name-servers 8.8.8.8;
}
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$ more /var/lib/dhcpd/dhcpd.leases |
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Sample entries from dhcpd.leases
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host 015016131b12_host {
dynamic;
hardware ethernet 01:50:16:13:1b:62;
fixed-address 192.168.1.2;
supersede routers = c0:a8:00:01;
supersede subnet-mask = ff:ff:ff:00;
}
host 01161e7c189f_host {
dynamic;
hardware ethernet 01:16:1e:7c:18:9f;
fixed-address 192.168.1.2;
supersede subnet-mask = ff:ff:ff:00;
}
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cat /etc/sysconfig/dhcpd | |
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/etc/sysconfig/dhcpd
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\# Command line options here DHCPDARGS="eth1 eth1.2 eth1.3 eth1.4 ... eth1.n" |
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ps -ef|grep dhcp
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tcpdump -vv -lenx udp port bootps or udp port bootpc |
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Check switch configuration
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# ip route
2.2.2.0/24 via 192.168.0.250 dev eth0
192.168.0.0/24 dev eth0 proto kernel scope link src 192.168.0.2
1.1.1.0/24 via 192.168.0.250 dev eth0
default via 192.168.0.1 dev eth0
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If the routes are not present, continue to check the configuration as described below.
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Check that the following two files exist on the system and are not empty:
/etc/dhclient.conf
/etc/dhclient-exit-hooks
The contents of these files should be as described in Configuring DHCP#Configure CentOS VM Template to Receive Static Routes by DHCP