Nepodařilo se spustit LSB:Vyvolat/spustit síť – při restartování síťové služby CentOS/RHEL (klient DHCP)

Problém

Nelze spolehlivě spustit síť na serveru při použití DHCP:

# sudo /etc/init.d/network restart
Restarting network (via systemctl): Job for network.service failed because the control process exited with error code. 
See "systemctl status network.service" and "journalctl -xe" for details.
[FAILED]

# journalctl -xe
Nov 29 18:57:42 hostaname.domain.com dhclient[37653]: exiting.
Nov 29 18:57:42 hostaname.domain.com network[37498]: [FAILED]
Nov 29 18:57:42 hostaname.domain.com network[37498]: RTNETLINK answers: File
Nov 29 18:57:42 hostaname.domain.com network[37498]: RTNETLINK answers: File
Nov 29 18:57:42 hostaname.domain.com network[37498]: RTNETLINK answers: File
Nov 29 18:57:42 hostaname.domain.com network[37498]: RTNETLINK answers: File
Nov 29 18:57:42 hostaname.domain.com network[37498]: RTNETLINK answers: File
Nov 29 18:57:42 hostaname.domain.com network[37498]: RTNETLINK answers: File
Nov 29 18:57:42 hostaname.domain.com network[37498]: RTNETLINK answers: File
Nov 29 18:57:42 hostaname.domain.com network[37498]: RTNETLINK answers: File
Nov 29 18:57:42 hostaname.domain.com network[37498]: RTNETLINK answers: File
Nov 29 18:57:42 hostaname.domain.com systemd[1]: network.service: control pr
Nov 29 18:57:42 hostaname.domain.com systemd[1]: Failed to start LSB: Bring
-- Subject: Unit network.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit network.service has failed.
--
-- The result is failed.
Nov 29 18:57:42 hostaname.domain.com systemd[1]: Unit network.service entere
Nov 29 18:57:42 hostaname.domain.com systemd[1]: network.service failed.
Nov 29 18:57:42 hostaname.domain.com polkitd[36998]: Unregistered Authentica

# sudo systemctl status -l network.service
● network.service - LSB: Bring up/down networking
Loaded: loaded (/etc/rc.d/init.d/network; bad; vendor preset: disabled)
Active: failed (Result: exit-code) since Mon 2016-12-12 12:48:04 EST; 28s ago
Docs: man:systemd-sysv-generator(8)
Process: 17797 ExecStop=/etc/rc.d/init.d/network stop (code=exited, status=0/SUCCESS)
Process: 18067 ExecStart=/etc/rc.d/init.d/network start (code=exited, status=1/FAILURE)

Dec 12 12:47:58 hostname.domain.com network[18067]: [FAILED]
Dec 12 12:47:58 hostname.domain.com network[18067]: Bringing up interface eth1:
Dec 12 12:48:04 hostname.domain.com network[18067]: Determining IP information for eth1... failed; no link present. Check cable?
Dec 12 12:48:04 hostname.domain.com network[18067]: [FAILED]
Dec 12 12:48:04 hostname.domain.com network[18067]: /etc/rc.d/init.d/network: line 88: ifcfg-eth0:DEVICE=eth0: command not found
Dec 12 12:48:04 hostname.domain.com network[18067]: /etc/rc.d/init.d/network: line 89: ifcfg-eth0:TYPE=Ethernet: command not found
Dec 12 12:48:04 hostname.domain.com systemd[1]: network.service: control process exited, code=exited status=1
Dec 12 12:48:04 hostname.domain.com systemd[1]: Failed to start LSB: Bring up/down networking.
Dec 12 12:48:04 hostname.domain.com systemd[1]: Unit network.service entered failed state.
Dec 12 12:48:04 hostname.domain.com systemd[1]: network.service failed.

konfigurační soubor sítě:

# less /etc/sysconfig/network-scripts/ifcfg-eth0
# Generated by parse-kickstart
IPV6INIT=yes
BOOTPROTO=dhcp
DEVICE=eth0
ONBOOT=yes
UUID=ccb107d4-4be6-453b-80f2-f803acc5f897
TYPE=Ethernet
DEFROUTE=yes
IPV4_FAILURE_FATAL=no
IPV6_AUTOCONF=yes
IPV6_DEFROUTE=yes
IPV6_FAILURE_FATAL=no
NAME="System eth0"
PEERDNS=yes
PEERROUTES=yes
DHCP_HOSTNAME=
IPV6_PEERDNS=yes
IPV6_PEERROUTES=yes

Řešení

Systém CentOS/RHEL nakonfigurovaný pro síť DHCP nezíská IP adresu při restartování síťové služby. Přidávání parametru PERSISTENT_DHCLIENT do konfiguračního souboru síťového rozhraní zajišťuje, že klient Oracle Linux DHCP (dhclient) konzistentně požaduje zapůjčení IP adresy ze serveru DHCP.

1. Připojte PERSISTENT_DHCLIENT direktiva v /etc/sysconfig/network soubor takto:

# vi /etc/sysconfig/network
NETWORKING=yes
PERSISTENT_DHCLIENT=yes

2. Restartujte síťové služby:

# /sbin/service network restart              ## For CentOS/RHEL 5/6
# /usr/bin/systemctl restart network         ## For CentOS/RHEL 7/8