From: Xunlei Pang xlpang@redhat.com
Currently kdump uses dracut's "nameserver=" command to hande DNS, it is acquired both from ifcfg files and "/etc/resolv.conf".
This is improper for dhcp cases, as "/etc/resolv.conf" is generated by dhcp, the proper logic should be: 1) For static cases, DNS can be acquired from corresponding ifcfg file. 2) For dhcp cases, DNS is normally generated by dhcp, but extra DNS can still be specified in the ifcfg files mannually. 3) For special user-assigned DNS not specified in any ifcfg file, we can pass it to dracut via "nameserver=".
This patch improves the logic using the following "ip=" command format provided by dracut: ip=<client-IP>:[<peer>]:<gateway-IP>:<netmask>:<client_hostname>: <interface>:{none|off|dhcp|on|any|dhcp6|auto6|ibft}[:[<dns1>][:<dns2>]]
Signed-off-by: Xunlei Pang xlpang@redhat.com --- dracut-module-setup.sh | 46 ++++++++++++++++++++++++---------------------- 1 file changed, 24 insertions(+), 22 deletions(-)
diff --git a/dracut-module-setup.sh b/dracut-module-setup.sh index 4cd7107..a18fdc0 100755 --- a/dracut-module-setup.sh +++ b/dracut-module-setup.sh @@ -63,26 +63,19 @@ kdump_is_vlan() { }
# $1: netdev name -kdump_setup_dns() { - local _nameserver _dns - local _dnsfile=${initdir}/etc/cmdline.d/42dns.conf - . /etc/sysconfig/network-scripts/ifcfg-$1 - - [ -n "$DNS1" ] && echo "nameserver=$DNS1" > "$_dnsfile" - [ -n "$DNS2" ] && echo "nameserver=$DNS2" >> "$_dnsfile" +# return pattern ":<dns1>[<:dns2>]" if not "" +kdump_get_dns_from_ifcfg() { + local _dns
- while read content; - do - _nameserver=$(echo $content | grep ^nameserver) - [ -z "$_nameserver" ] && continue + unset DNS1 DNS2 + if [ -e /etc/sysconfig/network-scripts/ifcfg-$1 ]; then + . /etc/sysconfig/network-scripts/ifcfg-$1 + fi
- _dns=$(echo $_nameserver | cut -d' ' -f2) - [ -z "$_dns" ] && continue + [ -n "$DNS1" ] && _dns=${_dns}:$(echo $DNS1) + [ -n "$DNS2" ] && _dns=${_dns}:$(echo $DNS2)
- if [ ! -f $_dnsfile ] || [ ! $(cat $_dnsfile | grep -q $_dns) ]; then - echo "nameserver=$_dns" >> "$_dnsfile" - fi - done < "/etc/resolv.conf" + echo -n "${_dns}" | cut -d':' -f1,2,3 }
#$1: netdev name @@ -254,22 +247,27 @@ kdump_setup_znet() { # Setup dracut to bringup a given network interface kdump_setup_netdev() { local _netdev=$1 _srcaddr=$2 - local _static _proto _ip_conf _ip_opts _ifname_opts + local _static _proto _ip_conf _ip_opts _ifname_opts _ifcfg_dns + local _global_dnsfile=${initdir}/etc/cmdline.d/42dns.conf
if [ "$(uname -m)" = "s390x" ]; then kdump_setup_znet $_netdev fi
- _netmac=$(kdump_get_mac_addr $_netdev) + # Using below "ip=" command format provided by dracut: + # ip=<client-IP>:[<peer>]:<gateway-IP>:<netmask>:<client_hostname>: + # <interface>:{none|off|dhcp|on|any|dhcp6|auto6|ibft}[:[<dns1>][:<dns2>]] _static=$(kdump_static_ip $_netdev $_srcaddr) if [ -n "$_static" ]; then _proto=none else _proto=dhcp + _static=":::::" fi
+ _ifcfg_dns=$(kdump_get_dns_from_ifcfg $_netdev) _ip_conf="${initdir}/etc/cmdline.d/40ip.conf" - _ip_opts=" ip=${_static}$(kdump_setup_ifname $_netdev):${_proto}" + _ip_opts=" ip=${_static}$(kdump_setup_ifname $_netdev):${_proto}${_ifcfg_dns}"
# dracut doesn't allow duplicated configuration for same NIC, even they're exactly the same. # so we have to avoid adding duplicates @@ -278,6 +276,12 @@ kdump_setup_netdev() { if [ ! -f $_ip_conf ] || ! grep -q $_ip_opts $_ip_conf &&\ ! grep -q "ip=[^[:space:]]*$_netdev" /proc/cmdline; then echo "$_ip_opts" >> $_ip_conf + # In case of no DNS specified by iscsi. + if [ -n "${_ifcfg_dns}" ]; then + _ifcfg_dns=${_ifcfg_dns##:} + echo "nameserver=${_ifcfg_dns%%:*}" >> ${_global_dnsfile} + [ "${_ifcfg_dns}" = "${_ifcfg_dns%%:*}" ] || echo "nameserver=${_ifcfg_dns##*:}" >> ${_global_dnsfile} + fi fi
if kdump_is_bridge "$_netdev"; then @@ -292,8 +296,6 @@ kdump_setup_netdev() { _ifname_opts=" ifname=$(kdump_setup_ifname $_netdev):$(kdump_get_mac_addr $_netdev)" echo "$_ifname_opts" >> $_ip_conf fi - - kdump_setup_dns "$_netdev" }
get_ip_route_field()