To answer your questios: 1. network is Intranet not internet. 2. servers CPU and I/O are very light. We did use "sar -u" and sar -b to check. 3. is NOT only one server has this network slow problem. at least 4 to 5 servers on that rack all report slow. it is NOT possible all servers on that rack are all heavy load. --- 11/3/28 (一)，Emmanuel Noobadmin <centos.admin at gmail.com> 寫道： > 寄件者: Emmanuel Noobadmin <centos.admin at gmail.com> > 主旨: Re: [CentOS] centos server network speed check??? > 收件者: "CentOS mailing list" <centos at centos.org> > 日期: 2011年3月28日,一,下午5:45 > On 3/29/11, mcclnx mcc <mcclnx at yahoo.com.tw> > wrote: > > we have several servers on same rack and servers are > all inside firewall. > > Centos version from 4.X to 5.X. sometime the > connection are very slow > > (compare to servers on other racks also inside > firewall). > > > > we discuss with network engineer he ask us use "ping" > and traceroute" to > > check. Both tools response time are good but if > we connect through > > application like Web browser, database, or DELL OPMN > tool. The response > > time is very very slow. > > Are you connecting to the servers from within the same > network/building or via Internet? > > If the ping times are good, it could be the servers are too > heavily > loaded, whether due to too many users or inefficient > applications. So > they would respond very slowly to requests although there > is no > network problem. > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos >