Shell
Logic
for
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| for file in ./*
do
if test -f $file
then
echo $file is file
fi
if test -d $file
then
echo $file is dictionary
fi
done
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Network
DNS
DNS刷新缓存
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| service nscd restart
service dnsmasq restart
rndc restart
|
查看某个record 何时才能失效,假设你的默认dns server 不是authoritative server
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| dig +nocmd +noall +answer www.google.com
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查看某个record 从authoritative server 请求一个record 时被设置的ttl
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| dig @ns1.google.com +nocmd www.google.com +noall +answer
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Proxy
/etc/profile
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2
| export http_proxy=xxx
export https_proxy=xxx
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tc
See linux 下使用 tc 模拟网络延迟和丢包
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| # 将 eth0 网卡的传输设置为延迟 100 毫秒发送
tc qdisc add dev eth0 root netem delay 100ms
# 删除上面配置
tc qdisc del dev eth0 root netem delay 100ms
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Common
Date & Time
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| # date +%Y%m%d
20190613
|