Linux-osion sisältö:

Ubuntun asennus

Linux DHCP

Linux PXE

Linux Preseed

Etusivu

Linux ja DHCP-palvelin

DHCP:n asennus tehtiin luokassa 5013 1.9.2009 klo 8-12 välillä. Kokonaisuudessaan asennus (ongelmat mukaanluettuina) vei noin 2 tuntia.

DHCP:n asennus

Pohjana asennukseen käytin Teron ohjesivua.

Asennuksen vaiheet:

1. ajettiin 'sudo apt-get install dhcp3-server'

2. ajettiin 'sudo nano /etc/default/dhcp3-server' ja muutettiin konffissa 'INTERFACES="eth0" ' muotoon 'INTERFACES="eth2" ' joka oli käytössä Ubuntussa (tieto haettu komennolla 'ifconfig')

3. poistettiin oletus 'mv dhcpd.conf dhcpd.conf.1' ja tehtiin uusi conffi (kohta 4.)

4. muokattiin (nano /etc/dhcp3/dhcpd.conf) ja liitettiin Teron malli-konffi (paste):

# Don't set "authoritative" until everything else is correct in dhcpd.conf
#authoritative;
# Warning: this overrides other DHCP servers
# Default options in Ubuntu:
ddns-update-style none;
default-lease-time 600;
max-lease-time 7200;
log-facility local7;
# Subnet row defines server's network card. Also set in "/etc/default/dhcp3-server"
# 'ifconfig' shows subnet (ipaddress, zeroes as in mask) and netmask
subnet 172.28.0.0 netmask 255.255.0.0 {
host terotestaa {
# 'ping target_host', 'arp' shows MAC address
# only give DHCP information to this computer:
hardware ethernet 00:0D:56:73:F0:0D;
# Basic DHCP info (see 'ifconfig', 'route', 'cat /etc/resolv.conf')
fixed-address 172.28.1.7;
option subnet-mask 255.255.0.0;
option routers 172.28.1.254;
option domain-name-servers 172.28.1.67, 172.28.1.69;
# Non-essential DHCP options
option domain-name "tielab.helia.fi";
}
}

Muutos Teron malliin:

# Don't set "authoritative" until everything else is correct in dhcpd.conf
authoritative;
# Warning: this overrides other DHCP servers
# Default options in Ubuntu:
ddns-update-style none;
default-lease-time 600;
max-lease-time 7200;
log-facility local7;
# Subnet row defines server's network card. Also set in "/etc/default/dhcp3-server"
# 'ifconfig' shows subnet (ipaddress, zeroes as in mask) and netmask
subnet 172.28.0.0 netmask 255.255.0.0 {
host mliikama {
# 'ping target_host', 'arp' shows MAC address
# only give DHCP information to this computer:
hardware ethernet 00:19:b9:cc:ed:50;
# Basic DHCP info (see 'ifconfig', 'route', 'cat /etc/resolv.conf')
fixed-address 172.28.1.142;
option subnet-mask 255.255.0.0;
option routers 172.28.1.254;
option domain-name-servers 172.28.1.69;
# Non-essential DHCP options
option domain-name "tielab.helia.fi";
}
}

HUOM! Muista laittaa päälle authorative!

5. Mentiin toiselle työasemalle Live-CD:n kanssa

6. ajettiin 'sudo dhclient -r' (tai network manager - kuvakkeesta eth0 pois ja päälle). IP pysyi edelleen sitkeästi muodossa 172.28.1.X

7. ajettiin 'less /var/log/syslog' josta tuli seuraavanlaista infoa (viimeiset rivit):

Sep 1 10:24:40 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:5f:44:2f via eth2: network 172.28/16: no free leases
Sep 1 10:24:42 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.163 (172.28.2.69) from 00:0f:fe:5f:44:2f via eth2: unknown lease 172.28.1.163.
Sep 1 10:25:12 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:50:1b:90 via eth2: network 172.28/16: no free leases
Sep 1 10:25:14 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.178 (172.28.2.69) from 00:0f:fe:50:1b:90 via eth2: unknown lease 172.28.1.178.
Sep 1 10:25:45 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:5f:44:93 via eth2: network 172.28/16: no free leases
Sep 1 10:25:47 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.103 (172.28.2.69) from 00:0f:fe:5f:44:93 via eth2: unknown lease 172.28.1.103.
Sep 1 10:25:53 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:5f:45:2b via eth2: network 172.28/16: no free leases
Sep 1 10:25:55 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:5f:44:4b via eth2: network 172.28/16: no free leases
Sep 1 10:25:57 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.211 (172.28.2.69) from 00:0f:fe:5f:44:4b via eth2: unknown lease 172.28.1.211.
Sep 1 10:25:57 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.183 (172.28.2.69) from 00:0f:fe:5f:45:2b via eth2: unknown lease 172.28.1.183.
Sep 1 10:26:43 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:5f:44:93 via eth2: network 172.28/16: no free leases
Sep 1 10:26:45 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.103 (172.28.2.69) from 00:0f:fe:5f:44:93 via eth2: unknown lease 172.28.1.103.
Sep 1 10:27:02 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:5f:45:2b via eth2: network 172.28/16: no free leases
Sep 1 10:27:04 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.183 (172.28.2.69) from 00:0f:fe:5f:45:2b via eth2: unknown lease 172.28.1.183.
Sep 1 10:28:34 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:5f:43:0f via eth2: network 172.28/16: no free leases
Sep 1 10:28:35 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.227 (172.28.2.69) from 00:0f:fe:5f:43:0f via eth2: unknown lease 172.28.1.227.
Sep 1 10:28:50 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:5f:44:93 via eth2: network 172.28/16: no free leases
Sep 1 10:28:52 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:50:1b:90 via eth2: network 172.28/16: no free leases
Sep 1 10:28:54 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.103 (172.28.2.69) from 00:0f:fe:5f:44:93 via eth2: unknown lease 172.28.1.103.
Sep 1 10:28:54 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.178 (172.28.2.69) from 00:0f:fe:50:1b:90 via eth2: unknown lease 172.28.1.178.
Sep 1 10:29:49 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:5f:44:51 via eth2: network 172.28/16: no free leases
Sep 1 10:29:49 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.111 (172.28.2.69) from 00:0f:fe:5f:44:51 via eth2: unknown lease 172.28.1.111.
Sep 1 10:29:56 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:5f:43:0f via eth2: network 172.28/16: no free leases
Sep 1 10:29:57 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.157 (172.28.2.69) from 00:0f:fe:5f:43:0f via eth2: unknown lease 172.28.1.157.
Sep 1 10:30:01 mliikama-desktop /USR/SBIN/CRON[8385]: (root) CMD ([ -x /usr/sbin/update-motd ] && /usr/sbin/update-motd 2>/dev/null)
Sep 1 10:30:31 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:5f:18:b3 via eth2: network 172.28/16: no free leases
Sep 1 10:30:35 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.205 (172.28.2.69) from 00:0f:fe:5f:18:b3 via eth2: unknown lease 172.28.1.205.
Sep 1 10:31:22 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:5f:43:0f via eth2: network 172.28/16: no free leases
Sep 1 10:31:23 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.195 (172.28.2.69) from 00:0f:fe:5f:43:0f via eth2: unknown lease 172.28.1.195.
Sep 1 10:31:45 mliikama-desktop dhcpd: DHCPDISCOVER from 00:0f:fe:5f:44:2f via eth2: network 172.28/16: no free leases
Sep 1 10:31:47 mliikama-desktop dhcpd: DHCPREQUEST for 172.28.1.163 (172.28.2.69) from 00:0f:fe:5f:44:2f via eth2: unknown lease 172.28.1.163.

Tässä vaiheessa hain tietoa Googlesta (hakusanat: no free leases), joista ei lopulta ollut apua ongelman selvittämiseen.

Teron neuvoilla tein muutokset dhcpd.conf:iin seuraavasti:

Tämän jälkeen DHCP-palvelin antoi asiakaskoneelle IP:ksi 172.28.0.142 ja asennus oli onnistunut (myös esim. selain toimi).


DHCP:n asennuksessa haettuja tietoja

DHCP:n asennusta varten hain isäntäkoneella (eli ts. työasemalla, jolle DHCP-palvelin asennettiin) tietoja seuraavin tuloksin:

 

mliikama@mliikama-desktop:~$ arp
Address HWtype HWaddress Flags Mask Iface
oes2.tielab.helia.fi ether 00:19:b9:cc:ed:50 C eth2

mliikama@mliikama-desktop:~$ sudo ifconfig

eth2 Link encap:Ethernet HWaddr 00:0f:fe:5f:44:41
inet addr:172.28.1.142 Bcast:172.28.255.255 Mask:255.255.0.0
inet6 addr: fe80::20f:feff:fe5f:4441/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:25240 errors:0 dropped:0 overruns:0 frame:0
TX packets:14529 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:25837392 (25.8 MB) TX bytes:1681801 (1.6 MB)
Memory:f0500000-f0520000

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:4 errors:0 dropped:0 overruns:0 frame:0
TX packets:4 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:240 (240.0 B) TX bytes:240 (240.0 B)

mliikama@mliikama-desktop:~$ route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
172.28.0.0 * 255.255.0.0 U 1 0 0 eth2
link-local * 255.255.0.0 U 1000 0 0 eth2
default 172.28.1.254 0.0.0.0 UG 0 0 0 eth2

 

mliikama@mliikama-desktop:~$ cat /etc/resolv.conf
# Generated by NetworkManager
domain tielab.helia.fi
search tielab.helia.fi
nameserver 172.28.2.69