一、按你要求修改部份源程序，在此举例修改syslimits.h文件的NGROUPS_MAX参数，NGROUPS_MAX涉及samba的用户组数，默认最多只有16个组，如果你的组超过了16个，就要修改此参数，然后重新编译内核了。
[[email protected] ~]# vi /usr/src/sys/sys/syslimits.h
change:
#define NGROUPS_MAX 16
to:
#define NGROUPS_MAX 64
:wq
二、到内核配置文件目录
(1)如果是AMD64位的系统，就要cd /usr/src/sys/amd64/conf/此例是32位系统，所以是到i386目录
[[email protected] ~]# cd /usr/src/sys/i386/conf/
(2)拷贝默认的GENERIC内核配置文件为newkernel
[[email protected] ~]# cp GENERIC newkernel
(3)然后修改newkernel配置文件，以下是我加入的参数，如参数功能自己网上查查吧，这里不做详解了！
[root@www.itkylin.com ~]# vi newkernel
ident SMP-GENERIC options SMP options MPTABLE_FORCE_HTT options QUOTA options COMPAT_FREEBSD5 options UNIONFS # Union filesystem device bktr options IPFIREWALL_DEFAULT_TO_ACCEPT options IPFIREWALL_FORWARD options IPFIREWALL_VERBOSE options IPFIREWALL_VERBOSE_LIMIT device carp device pf device pflog device pfsync device vlan device gre options IPSTEALTH options TCP_DROP_SYNFIN #drop TCP packets with SYN+FIN options GEOM_UZIP options GEOM_LABEL options INCLUDE_CONFIG_FILE options NETGRAPH #netgraph(4) system options NETGRAPH_ASYNC options NETGRAPH_BPF options NETGRAPH_BRIDGE options NETGRAPH_CISCO options NETGRAPH_ECHO options NETGRAPH_ETHER options NETGRAPH_FRAME_RELAY options NETGRAPH_HOLE options NETGRAPH_IFACE options NETGRAPH_KSOCKET options NETGRAPH_LMI options NETGRAPH_MPPC_ENCRYPTION options NETGRAPH_ONE2MANY options NETGRAPH_PPP options NETGRAPH_PPPOE options NETGRAPH_PPTPGRE options NETGRAPH_RFC1490 options NETGRAPH_SOCKET options NETGRAPH_TEE options NETGRAPH_TTY options NETGRAPH_UI options NETGRAPH_VJC device ubsa device ucom options FAST_IPSEC device crypto # core crypto support device cryptodev # /dev/crypto for access to h/w device rndtest # FIPS 140-2 entropy tester device hifn # Hifn 7951, 7781, etc. options HIFN_DEBUG # enable debugging support: hw.hifn.debug options HIFN_RNDTEST # enable rndtest support device ubsec # Broadcom 5501, 5601, 58xx options ALTQ options ALTQ_CBQ options ALTQ_RED options ALTQ_RIO options ALTQ_HFSC options ALTQ_PRIQ options ALTQ_NOPCC # Required for SMP builds !! #Bridging device if_bridge options MSGMNB=8192 # max # of bytes in a queue options MSGMNI=40 # number of message queue identifiers options MSGSEG=512 # number of message segments per queue options MSGSSZ=32 # size of a message segment options MSGTQL=2048 # max messages in system device tap device hme #Needed for FreeSBIE 2 options NULLFS device speaker options DEVICE_POLLING options SC_DISABLE_REBOOT options ZERO_COPY_SOCKETS options TCP_SIGNATURE #To make an SMP kernel, the next two lines are needed #options SMP # Symmetric MultiProcessor Kernel #Allow gmirror to function #options GEOM_MIRROR #options GEOM_MBR #options itkylin.com #options NF_SOCKOPT options QUOTA device tap options IPFILTER options IPFILTER_LOG options IPFILTER_DEFAULT_BLOCK options SC_DISABLE_REBOOT
三、执行以下命令开始编译安装内核
[[email protected] ~]# cd /usr/src/sys/i386/conf/
[[email protected] ~]# config newkernel
[[email protected] ~]#cd ../compile/newkernel
[[email protected] ~]#make cleandepend
[[email protected] ~]#make depend
[[email protected] ~]#make
[[email protected] ~]#make install
四、因为内核开启了pf防火墙功能，所以要修改sysctl.conf和rc.conf配置文件
[[email protected] ~]#vi /etc/sysctl.conf
kern.timecounter.hardware=TSC
net.inet.tcp.path_mtu_discovery=0
net.inet.ip.forwarding=1
:wq
[[email protected] ~]#vi /etc/rc.conf
#Enable PF firewall
pf_enable=”YES”
pf_rules=”/etc/pf.conf”
pf_flags=””
#Enable PF logging
pflog_enable=”YES”
pflog_logfile=”/var/log/pflog”
pflog_flags=””
:wq
[[email protected] ~]#vi /etc/pf.conf
pass in all
pass out all
:wq
五、重新启动系统后会用新的内核了！
[[email protected] ~]#reboot