我使用 ssh (putty) 进行远程连接。90% 的时间里，当我尝试运行与网络相关的命令时，服务器都会重新启动。它会在几分钟内不可用，然后又恢复正常。当我尝试 svn checkout 时，我注意到了第一个问题。我尝试重新启动网络服务，但 putty 一直显示“网络错误：软件导致连接中止”。这是网络中断还是服务器关闭并重新启动。连接重新建立大约需要 3 分钟。
知道发生什么事了吗？
这是 /var/log/messages
Jan 26 01:04:43 appserver yum[8865]: Installed: mod_dav_svn-1.6.11-2.el6_1.4.x86_64
Jan 26 13:40:03 appserver NetworkManager[1655]: (eth1): device state change: 8 -> 3 (reason 39)
Jan 26 13:40:03 appserver NetworkManager[1655]: (eth1): deactivating device (reason: 39).
Jan 26 13:40:03 appserver avahi-daemon[1669]: Withdrawing address record for 134.245.322.12 on eth1.
Jan 26 13:40:03 appserver avahi-daemon[1669]: Leaving mDNS multicast group on interface eth1.IPv4 with address 134.245.322.12.
Jan 26 13:40:03 appserver avahi-daemon[1669]: Interface eth1.IPv4 no longer relevant for mDNS.
Jan 26 13:40:03 appserver kernel: lo: Disabled Privacy Extensions
Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) starting connection 'System eth1'
Jan 26 13:40:04 appserver NetworkManager[1655]: (eth1): device state change: 3 -> 4 (reason 0)
Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 1 of 5 (Device Prepare) scheduled...
Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 1 of 5 (Device Prepare) started...
Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 2 of 5 (Device Configure) scheduled...
Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 1 of 5 (Device Prepare) complete.
Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 2 of 5 (Device Configure) starting...
Jan 26 13:40:04 appserver NetworkManager[1655]: (eth1): device state change: 4 -> 5 (reason 0) Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 2 of 5 (Device Configure) successful. Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 3 of 5 (IP Configure Start) scheduled.
Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 2 of 5 (Device Configure) complete.
Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 3 of 5 (IP Configure Start) started...
Jan 26 13:40:04 appserver NetworkManager[1655]: (eth1): device state change: 5 -> 7 (reason 0)
Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 4 of 5 (IP4 Configure Get) scheduled...
Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 3 of 5 (IP Configure Start) complete. Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 4 of 5 (IP4 Configure Get) started...
Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 5 of 5 (IP Configure Commit) scheduled...
Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 4 of 5 (IP4 Configure Get) complete.
Jan 26 13:40:04 appserver NetworkManager[1655]: Activation (eth1) Stage 5 of 5 (IP Configure Commit) started...
Jan 26 13:40:04 appserver avahi-daemon[1669]: Joining mDNS multicast group on interface eth1.IPv4 with address 134.245.322.12.
Jan 26 13:40:04 appserver avahi-daemon[1669]: New relevant interface eth1.IPv4 for mDNS.
Jan 26 13:40:04 appserver avahi-daemon[1669]: Registering new address record for 134.245.322.12 on eth1.IPv4.
Jan 26 13:40:05 appserver NetworkManager[1655]: (eth1): device state change: 7 -> 8 (reason 0)
Jan 26 13:40:05 appserver NetworkManager[1655]: Policy set 'System eth1' (eth1) as default for IPv4 routing and DNS.
Jan 26 13:40:05 appserver NetworkManager[1655]: Activation (eth1) successful, device activated.
Jan 26 13:40:05 appserver NetworkManager[1655]: Activation (eth1) Stage 5 of 5 (IP Configure Commit) complete.
Jan 26 13:47:03 appserver NetworkManager[1655]: (eth1): device state change: 8 -> 3 (reason 39)
Jan 26 13:47:03 appserver NetworkManager[1655]: (eth1): deactivating device (reason: 39).
Jan 26 13:47:03 appserver avahi-daemon[1669]: Withdrawing address record for 134.245.322.12 on eth1.
Jan 26 13:47:03 appserver avahi-daemon[1669]: Leaving mDNS multicast group on interface eth1.IPv4 with address 134.245.322.12.
Jan 26 13:47:03 appserver avahi-daemon[1669]: Interface eth1.IPv4 no longer relevant for mDNS.
Jan 26 13:47:04 appserver kernel: lo: Disabled Privacy Extensions