我們經(jīng)常會通過find命令進(jìn)行批量操作，如：批量刪除舊文件、批量修改、基于時(shí)間的文件統(tǒng)計(jì)、基于文件大小的文件統(tǒng)計(jì)等，在這些操作當(dāng)中，由于rm刪除操作會導(dǎo)致目錄結(jié)構(gòu)變化，如果要通過find結(jié)合rm的操作寫成腳本，就會遇到一些麻煩，本文通過一個(gè)例子為大家進(jìn)行介紹。
系統(tǒng)環(huán)境：
SUSE Linux Enterprise Server 11 或
Red Hat Enterprise Linux
問題癥狀：
客戶現(xiàn)場有一個(gè)自動化的腳本，有以下的find語句，每天運(yùn)行以刪除某個(gè)目錄下7天以前的文件或目錄，這些目錄都是按時(shí)間順序生成PostgreSQL數(shù)據(jù)庫的WAL日志及其錯(cuò)誤日志pg_log：
/bin/find /enterprisedb_backup/postgresql/ -mtime +7 -exec /bin/rm -rf '{}' /;
運(yùn)行過程中，間歇性地出現(xiàn)以下錯(cuò)誤：
[root@edb ~]# /bin/find /enterprisedb_backup/postgresql/ -mtime +7 -exec /bin/rm -rf {} /;/bin/find: `/enterprisedb_backup/postgresql/network-scripts': No such file or directory[root@edb ~]# echo $?1顯然，以上命令返回了錯(cuò)誤的結(jié)果，但客戶反映說，以上腳本運(yùn)行后目錄下7天前的數(shù)據(jù)的確備刪除了。
問題分析：
進(jìn)行故障重現(xiàn)，在另一臺服務(wù)器中通過模擬數(shù)據(jù)單獨(dú)運(yùn)行find命令分析此問題，測試過程如下：
1.模擬數(shù)據(jù)
[root@edbnode1 ~]# dateWed Jun 18 23:08:18 CST 2014[root@edbnode1 ~]# cp -rcp /etc/sysconfig/network-scripts/ /enterprisedb_backup/postgresql/[root@edbnode1 ~]# cp -rcp /etc/init.d/iptables /enterprisedb_backup/postgresql/## 以上通過 cp -rcp 命令使得拷貝到目標(biāo)目錄的數(shù)據(jù)保持包括：建立時(shí)間、用戶權(quán)根等信息，以模擬出一個(gè)舊文件及一個(gè)舊目錄[root@edbnode1 ~]# ll /enterprisedb_backup/postgresql/total 16-rwxr-xr-x. 1 root root 9409 Oct 31 2012 iptablesdrwxr-xr-x. 2 root root 4096 Jun 18 2013 network-scripts## 以上可以看到iptables文件是2012年建立的，network-scripts是2013年建立的，都遠(yuǎn)遠(yuǎn)超過了7天[root@edbnode1 ~]# ll /enterprisedb_backup/postgresql/*-rwxr-xr-x. 1 root root 9409 Oct 31 2012 /enterprisedb_backup/postgresql/iptables/enterprisedb_backup/postgresql/network-scripts:total 212-rw-r--r--. 1 root root 159 Jun 18 2013 ifcfg-eth0-rw-r--r--. 1 root root 203 Jun 18 2013 ifcfg-eth1-rw-r--r--. 1 root root 203 Jun 18 2013 ifcfg-eth2-rw-r--r--. 1 root root 254 Jan 9 2013 ifcfg-lolrwxrwxrwx. 1 root root 20 Jun 18 2013 ifdown -> ../../../sbin/ifdown-rwxr-xr-x. 1 root root 627 Jan 9 2013 ifdown-bnep-rwxr-xr-x. 1 root root 5397 Jan 9 2013 ifdown-eth-rwxr-xr-x. 1 root root 781 Jan 9 2013 ifdown-ippp-rwxr-xr-x. 1 root root 4168 Jan 9 2013 ifdown-ipv6lrwxrwxrwx. 1 root root 11 Jun 18 2013 ifdown-isdn -> ifdown-ippp-rwxr-xr-x. 1 root root 1481 Jan 9 2013 ifdown-post-rwxr-xr-x. 1 root root 1064 Jan 9 2013 ifdown-ppp-rwxr-xr-x. 1 root root 835 Jan 9 2013 ifdown-routes-rwxr-xr-x. 1 root root 1370 Jan 9 2013 ifdown-sit-rwxr-xr-x. 1 root root 1434 Jan 9 2013 ifdown-tunnellrwxrwxrwx. 1 root root 18 Jun 18 2013 ifup -> ../../../sbin/ifup-rwxr-xr-x. 1 root root 12365 Jan 9 2013 ifup-aliases-rwxr-xr-x. 1 root root 859 Jan 9 2013 ifup-bnep-rwxr-xr-x. 1 root root 10157 Jan 9 2013 ifup-eth-rwxr-xr-x. 1 root root 11971 Jan 9 2013 ifup-ippp-rwxr-xr-x. 1 root root 10401 Jan 9 2013 ifup-ipv6lrwxrwxrwx. 1 root root 9 Jun 18 2013 ifup-isdn -> ifup-ippp-rwxr-xr-x. 1 root root 727 Jan 9 2013 ifup-plip-rwxr-xr-x. 1 root root 954 Jan 9 2013 ifup-plusb-rwxr-xr-x. 1 root root 2364 Jan 9 2013 ifup-post-rwxr-xr-x. 1 root root 4154 Jan 9 2013 ifup-ppp-rwxr-xr-x. 1 root root 1925 Jan 9 2013 ifup-routes-rwxr-xr-x. 1 root root 3499 Jan 9 2013 ifup-sit-rwxr-xr-x. 1 root root 2488 Jan 9 2013 ifup-tunnel-rwxr-xr-x. 1 root root 3770 Jan 9 2013 ifup-wireless-rwxr-xr-x. 1 root root 4623 Jan 9 2013 init.ipv6-global-rwxr-xr-x. 1 root root 1125 Jan 9 2013 net.hotplug-rw-r--r--. 1 root root 13079 Jan 9 2013 network-functions-rw-r--r--. 1 root root 29853 Jan 9 2013 network-functions-ipv6## 以上可以看到network-script不是一個(gè)空的目錄，當(dāng)中還有文件，而且文件也都已經(jīng)是7天前建立的了
2.測試單獨(dú)模擬執(zhí)行腳本中的find + rm指令
[root@edbnode1 ~]# /bin/find /enterprisedb_backup/postgresql/ -mtime +7 -exec /bin/rm -rf {} /;/bin/find: `/enterprisedb_backup/postgresql/network-scripts': No such file or directory[root@edbnode1 ~]# echo $?1[root@edbnode1 ~]# ls /enterprisedb_backup/postgresql/[root@edbnode1 ~]#可以看到find操作的確返回了錯(cuò)誤的結(jié)果，但查看數(shù)據(jù)備份目錄發(fā)現(xiàn)，iptables文件及network-scripts目錄已經(jīng)正確刪除
3.由于數(shù)據(jù)已經(jīng)正確刪除，因此我們開始懷疑是由network-scripts目錄刪除后，find繼續(xù)嘗試刪除此目錄下其它文件，導(dǎo)致出不“No such file or directory”的錯(cuò)誤，因此需要于進(jìn)一步證實(shí)此猜想，重新執(zhí)行以上“第1步”中的數(shù)據(jù)環(huán)境模擬，并執(zhí)行以下操作，主要是將rm轉(zhuǎn)換成ls以展現(xiàn)整體運(yùn)行過程：
[root@edbnode1 ~]# cp -rcp /etc/sysconfig/network-scripts/ /enterprisedb_backup/postgresql/[root@edbnode1 ~]# cp -rcp /etc/init.d/iptables /enterprisedb_backup/postgresql/[root@edbnode1 ~]# /bin/find /enterprisedb_backup/postgresql/ -mtime +7 -exec /bin/ls {} /;ifcfg-eth0 ifcfg-lo ifdown-eth ifdown-isdn ifdown-routes ifup ifup-eth ifup-isdn ifup-post ifup-sit init.ipv6-global network-functions-ipv6ifcfg-eth1 ifdown ifdown-ippp ifdown-post ifdown-sit ifup-aliases ifup-ippp ifup-plip ifup-ppp ifup-tunnel net.hotplugifcfg-eth2 ifdown-bnep ifdown-ipv6 ifdown-ppp ifdown-tunnel ifup-bnep ifup-ipv6 ifup-plusb ifup-routes ifup-wireless network-functions/enterprisedb_backup/postgresql/network-scripts/ifup-plusb/enterprisedb_backup/postgresql/network-scripts/ifup-sit/enterprisedb_backup/postgresql/network-scripts/ifdown-post/enterprisedb_backup/postgresql/network-scripts/ifcfg-lo/enterprisedb_backup/postgresql/network-scripts/network-functions/enterprisedb_backup/postgresql/network-scripts/ifup-bnep/enterprisedb_backup/postgresql/network-scripts/ifup-ippp/enterprisedb_backup/postgresql/network-scripts/ifdown-sit/enterprisedb_backup/postgresql/network-scripts/ifdown-tunnel/enterprisedb_backup/postgresql/network-scripts/ifup-plip/enterprisedb_backup/postgresql/network-scripts/ifup-eth/enterprisedb_backup/postgresql/network-scripts/ifdown-ipv6/enterprisedb_backup/postgresql/network-scripts/ifdown-ippp/enterprisedb_backup/postgresql/network-scripts/ifup-aliases/enterprisedb_backup/postgresql/network-scripts/network-functions-ipv6/enterprisedb_backup/postgresql/network-scripts/ifup-ipv6/enterprisedb_backup/postgresql/network-scripts/ifup-post/enterprisedb_backup/postgresql/network-scripts/ifcfg-eth2/enterprisedb_backup/postgresql/network-scripts/ifcfg-eth1/enterprisedb_backup/postgresql/network-scripts/ifdown-ppp/enterprisedb_backup/postgresql/network-scripts/ifup-isdn/enterprisedb_backup/postgresql/network-scripts/ifcfg-eth0/enterprisedb_backup/postgresql/network-scripts/ifdown/enterprisedb_backup/postgresql/network-scripts/ifup-wireless/enterprisedb_backup/postgresql/network-scripts/ifup-ppp/enterprisedb_backup/postgresql/network-scripts/ifdown-eth/enterprisedb_backup/postgresql/network-scripts/init.ipv6-global/enterprisedb_backup/postgresql/network-scripts/ifdown-isdn/enterprisedb_backup/postgresql/network-scripts/ifup-tunnel/enterprisedb_backup/postgresql/network-scripts/ifdown-routes/enterprisedb_backup/postgresql/network-scripts/ifdown-bnep/enterprisedb_backup/postgresql/network-scripts/net.hotplug/enterprisedb_backup/postgresql/network-scripts/ifup/enterprisedb_backup/postgresql/network-scripts/ifup-routes/enterprisedb_backup/postgresql/iptables通過以上操作我們可以看到，find命令不單查詢了/enterprisedb_backup/postgresql/目錄，并且遍歷了所有子目錄，因此支持了我們的推斷
4.綜上所述基本定位問題所在
解決方案：
1.整理思路后，可以確認(rèn)，如果find只找出所需操作目錄的第1層文件及目錄即可解決此問題
2.通過偉大的 man 命令我們得到以下信息
-maxdepth levels Descend at most levels (a non-negative integer) levels of directories below the command line arguments. -maxdepth 0 means only apply the tests and actions to the command line arguments.
3.測試操作確認(rèn)修改為：
[root@edbnode1 ~]# /bin/find /enterprisedb_backup/postgresql/ -mtime +7 -maxdepth 1 -exec /bin/rm -rf {} /;/bin/find: warning: you have specified the -maxdepth option after a non-option argument -mtime, but options are not positional (-maxdepth affects tests specified before it as well as those specified after it). Please specify options before other arguments.這里意思是說：-mtime找到的信息可能會操過-maxdepth的范圍，在find操作中建議-maxdepth放在所有其他參數(shù)的前面
解決結(jié)果【完成】
以上這篇淺談Linux下通過find命令進(jìn)行rm文件刪除的小技巧就是小編分享給大家的全部內(nèi)容了，希望能給大家一個(gè)參考，也希望大家多多支持VEVB武林網(wǎng)。
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