环境Linux 安装杀毒软件clamav 0.97.6
#freshclam --升级时报错如下：
[root@logserver clamav]# ./bin/freshclam ClamAV update process started at Wed Oct 17 22:31:04 2012 WARNING: Can't query current.cvd.clamav.net WARNING: Invalid DNS reply. Falling back to HTTP mode. WARNING: Can't get information about database.clamav.net: Temporary failure in name resolution WARNING: Can't download main.cvd from database.clamav.net Trying again in 5 secs... ClamAV update process started at Wed Oct 17 22:31:09 2012 WARNING: Can't query current.cvd.clamav.net WARNING: Invalid DNS reply. Falling back to HTTP mode. WARNING: Can't get information about database.clamav.net: Temporary failure in name resolution WARNING: Can't download main.cvd from database.clamav.net Trying again in 5 secs... ClamAV update process started at Wed Oct 17 22:31:14 2012 WARNING: Can't query current.cvd.clamav.net WARNING: Invalid DNS reply. Falling back to HTTP mode. ERROR: Can't get information about database.clamav.net: Temporary failure in name resolution ERROR: Can't download main.cvd from database.clamav.net Giving up on database.clamav.net... Update failed. Your network may be down or none of the mirrors listed in /opt/clamav/etc/freshclam.conf is working. Check http://www.clamav.net/support/mirror-problem for possible reasons.
此时：
ping database.clamav.net 能拼通。
ping http://www.clamav.net/support/mirror-problem也能拼通。
个人经验：ClamAV的病毒库更新地址有很多。ClamAV更新病毒库时，以上回复我也见过。但它会自动找其他地址的，直到找到可以用的地址。
估计是DNS解析问题。
解决方法：
ping database.clamav.net 得到一个ip 如180.92.182.5 再然后改/etc/hosts这个文件。加入一行：
180.92.182.5 database.clamav.net
重启网络：service network restart
再升级
#freshclam
升级成功提示如下：
Database updated (1321737 signatures) from database.clamav.net (IP: 180.92.182.5)
最后我的这样能解决这个问题，你也可以试试这方法！