yum update
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* base: ftp.iij.ad.jp
* epel: ftp.iij.ad.jp
* extras: ftp.iij.ad.jp
* rpmforge: ftp.riken.jp
* updates: ftp.iij.ad.jp
Setting up Update Process
Resolving Dependencies
--> Running transaction check
---> Package iftop.i686 0:0.17-1.el6.rf will be updated
---> Package iftop.i386 0:1.0-0.1.pre2.el5 will be an update
--> Processing Dependency: libpcap.so.0.9.4 for package: iftop-1.0-0.1.pre2.el5.i386
---> Package iotop.noarch 0:0.3.2-3.el6 will be updated
---> Package iotop.noarch 0:0.4.1-2.el5 will be an update
--> Processing Dependency: python(abi) = 2.4 for package: iotop-0.4.1-2.el5.noarch
---> Package pptpd.i686 0:1.3.4-2.el6 will be updated
---> Package pptpd.i386 0:1.3.4-2.fc6 will be an update
--> Processing Dependency: ppp = 2.4.4 for package: pptpd-1.3.4-2.fc6.i386
---> Package python-ethtool.i686 0:0.6-1.el6 will be updated
---> Package python-ethtool.i386 0:0.6-2.el5 will be an update
--> Processing Dependency: python(abi) = 2.4 for package: python-ethtool-0.6-2.el5.i386
--> Finished Dependency Resolution
Error: Package: pptpd-1.3.4-2.fc6.i386 (poptop-stable)
           Requires: ppp = 2.4.4
           Installed: ppp-2.4.5-5.el6.i686 (@base)
               ppp = 2.4.5-5.el6
           Available: ppp-2.4.4-14.1.fc6.i386 (poptop-stable)
               ppp = 2.4.4-14.1.fc6
Error: Package: iftop-1.0-0.1.pre2.el5.i386 (epel)
           Requires: libpcap.so.0.9.4
Error: Package: iotop-0.4.1-2.el5.noarch (epel)
           Requires: python(abi) = 2.4
           Installed: python-2.6.6-29.el6.i686 (@anaconda-CentOS-201112130233.i386/6.2)
               python(abi) = 2.6
           Available: python26-2.6.8-1.el5.i386 (epel)
               python(abi) = 2.6
Error: Package: python-ethtool-0.6-2.el5.i386 (epel)
           Requires: python(abi) = 2.4
           Installed: python-2.6.6-29.el6.i686 (@anaconda-CentOS-201112130233.i386/6.2)
               python(abi) = 2.6
           Available: python26-2.6.8-1.el5.i386 (epel)
               python(abi) = 2.6
You could try using --skip-broken to work around the problem
You could try running: rpm -Va --nofiles --nodigest