使用 udev 自动重命名和编号 nic答案

【问题标题】：automatic renaming and numbering of nics using udev使用 udev 自动重命名和编号 nic
【发布时间】：2009-10-29 16:01:39
【问题描述】：

我正在编写一个 udev 规则，以自动重命名和编号具有特定 MAC 地址的 NIC。

生成的规则应该与75-persistent-net-generator.rules 几乎相同（匹配卡的 MAC 地址的前 3 个字节，将其命名为“mycard*”，具体取决于安装了该供应商的卡数量，将重命名规则写入70-persistent-net.rules)。

到目前为止，我已经走了多远：

# udev rules to name rename cards to mycard

ACTION!="add", GOTO="persistent_mycard_generator_end"
SUBSYSTEM!="net", GOTO="persistent_mycard_generator_end"

# ignore the interface if a name has already been set
NAME=="mycard*", GOTO="persistent_mycard_generator_end"

# device name whitelist
KERNEL!="eth*", GOTO="persistent_mycard_generator_end"

# read MAC address
ENV{MATCHADDR}="$attr{address}"

# match interface type
ENV{MATCHIFTYPE}="$attr{type}"

# ignore non mycard MAC addresses
ENV{MATCHADDR}!="00:11:22:*", GOTO="persistent_mycard_generator_end"

# default comment
ENV{COMMENT}=="", ENV{COMMENT}="mycard connected through ($attr{driver})"

#### THIS IS THE PART I DON'T GET ####

# write rule
DRIVERS=="?*", IMPORT{program}="write_net_rules"

# rename interface if needed
ENV{INTERFACE_NEW}=="?*", NAME="mycard*"

#### THIS IS THE END OF THE PART I DON'T GET ####

LABEL="persistent_mycard_generator_end

“我没有得到的部分”应该做的任务是将卡（假设它是 eth3）重命名为 mycard0，或者如果它是系统中具有匹配 MAC 地址 mycard1 的第二张卡，依此类推。

提前致谢，植物群

【问题讨论】：

标签： linux networking udev

【解决方案1】：

如果您在调用 write_net_rules 之前将 ENV{INTERFACE} 设置为“mycard0”，它将为您找到第一个未使用的 mycardN，为其写出规则，并返回 ENV{INTERFACE_NEW} 中的名称。

【讨论】：

差不多了。留下一个问题：写的规则有KERNEL==mycard* 而不是KERNEL==eth*，所以它没有被应用。我今天早上写了一个完整的解决方案，我回家后会发布。

【解决方案2】：

好的，这是我的解决方案（我已经使用 Debian 5.0 和 Ubuntu 9.04 对其进行了测试，所以我不确定它是否适用于其他发行版的 udev 实现）：

75-persistent-mycard-generator.rules

ACTION!="add", GOTO="persistent_mycard_generator_end"
SUBSYSTEM!="net", GOTO="persistent_mycard_generator_end"

# ignore the interface if a name has already been set
NAME=="?*", GOTO="persistent_mycard_generator_end"

# device name whitelist
KERNEL!="eth*", GOTO="persistent_mycard_generator_end"

# by default match on the MAC address and interface type
ENV{MATCHADDR}="$attr{address}"
ENV{MATCHIFTYPE}="$attr{type}"

# match interface dev_id
ATTR{dev_id}=="?*", ENV{MATCHDEVID}="$attr{dev_id}"

# by default match on the MAC address and interface type
ENV{MATCHADDR}="$attr{address}"
ENV{MATCHIFTYPE}="$attr{type}"

# match interface dev_id
ATTR{dev_id}=="?*", ENV{MATCHDEVID}="$attr{dev_id}"

# terminate processing if card is not a mycard
ENV{MATCHADDR}!="AA:BB:CC:*", GOTO="persistent_mycard_generator_end"

# provide nice comments for the generated rules
SUBSYSTEMS=="pci", ENV{COMMENT}="PCI device $attr{vendor}:$attr{device}"
SUBSYSTEMS=="pcmcia", ENV{COMMENT}="PCMCIA device $attr{card_id}:$attr{manf_id}"
SUBSYSTEMS=="usb", ENV{COMMENT}="USB device 0x$attr{idVendor}:0x$attr{idProduct}"
ENV{COMMENT}=="", ENV{COMMENT}="Unknown $env{SUBSYSTEM} device($env{DEVPATH})"
ATTRS{driver}=="?*", ENV{COMMENT}="$env{COMMENT} ($attr{driver})"

# add mycard to comment
ENV{COMMENT}="$env{COMMENT} (mycard)"

# set interface name to mycard0 (initially)
ENV{INTERFACE}="mycard0"

# generate and write the rule
DRIVERS=="?*", IMPORT{program}="write_mycard_rules"

# rename the interface if requested
ENV{INTERFACE_NEW}=="?*",NAME="$env{INTERFACE_NEW}"

LABEL="persistent_mycard_generator_end"

write_mycard_rules

RULES_FILE='/etc/udev/rules.d/70-persistent-net.rules'

. /lib/udev/hotplug.functions

interface_name_taken() {
    local value="$(find_all_rules 'NAME=' $INTERFACE)"
    if [ "$value" ]; then
        return 0
    fi
    return 1

}

find_next_available() {
    raw_find_next_available "$(find_all_rules 'NAME=' "$1")"
}

write_rule() {
    local match="$1"
    local name="$2"
    local comment="$3"

    {
    if [ "$PRINT_HEADER" ]; then
        PRINT_HEADER=
        echo "# This file was automatically generated by the $0"
        echo "# program run by the persistent-mycard-generator.rules rules file."
        echo "#"
        echo "# You can modify it, as long as you keep each rule on a single line."
    fi

    echo ""
    [ "$comment" ] && echo "# $comment"
    echo "SUBSYSTEM==\"net\", ACTION==\"add\"$match, NAME=\"$name\""
    } >> $RULES_FILE
}

if [ -z "$INTERFACE" ]; then
    echo "missing \$INTERFACE" >&2
    exit 1
fi

# Prevent concurrent processes from modifying the file at the same time.
lock_rules_file

# Check if the rules file is writeable.
choose_rules_file

# the DRIVERS key is needed to not match bridges and VLAN sub-interfaces
if [ "$MATCHADDR" ]; then
    match="$match, DRIVERS==\"?*\", ATTR{address}==\"$MATCHADDR\""
fi


if [ "$MATCHDRV" ]; then
    match="$match, DRIVERS==\"$MATCHDRV\""
fi

if [ "$MATCHDEVID" ]; then
    match="$match, ATTR{dev_id}==\"$MATCHDEVID\""
fi


if [ "$MATCHID" ]; then
    match="$match, KERNELS==\"$MATCHID\""
fi        

if [ "$MATCHIFTYPE" ]; then
    match="$match, ATTR{type}==\"$MATCHIFTYPE\""
fi


if [ -z "$match" ]; then
    echo "missing valid match" >&2
    unlock_rules_file
    exit 1
fi

basename=${INTERFACE%%[0-9]*}
match="$match, KERNEL==\"eth*\""
if [ "$INTERFACE_NAME" ]; then
    # external tools may request a custom name
    COMMENT="$COMMENT (custom name provided by external tool)"

    if [ "$INTERFACE_NAME" != "$INTERFACE" ]; then
        INTERFACE=$INTERFACE_NAME;
        echo "INTERFACE_NEW=$INTERFACE"
    fi
else
    # if a rule using the current name already exists, find a new name
    if interface_name_taken; then
        INTERFACE="$basename$(find_next_available "$basename[0-9]*")"
        echo "INTERFACE_NEW=$INTERFACE"
    fi
fi

write_rule "$match" "$INTERFACE" "$COMMENT"
unlock_rules_file
exit 0

最重要的更改是 75-persistent-mycard-generator.rules 中的 ENV{INTERFACE}="mycard0" 设置卡片应获取的名称，以及 write_mycard_rules 中的 match="$match, KERNEL==\"eth*\"" 强制 udev 不使用新名称覆盖使用的内核子系统。

【讨论】：