Hi, We have recently update kernel-xen on all of our hosts (3) and its vms all running fc6. kernel-xen 2.6.20-1.2962.fc6xen is doing good on two hosts and all its vms (10), however its giving lot of problem on third host. when i reboots the host into latest kernel-xen the domUs become unaccessible in a while hardly run for 10 minutes, 'xm list' still shows there status but i can't access it from outside. We are using loop back files for domUs File system, for testing i rebooted host into last working kernel 2.6.20-1.2952.fc6xen and domUs into latest kernel-xen and its doing pretty good, which mean latest kernel-xen is only giving problem at host side. when running 2.6.20-1.2962 on host it giving this in /var/log/messages Jul 12 10:42:45 xxxx kernel: xen_net: Memory squeeze in netback driver. Jul 12 10:42:50 xxxx kernel: printk: 4 messages suppressed. Jul 12 10:42:50 xxxx kernel: xen_net: Memory squeeze in netback driver. Jul 12 10:42:55 xxxx kernel: printk: 4 messages suppressed. Jul 12 10:42:55 xxxx kernel: xen_net: Memory squeeze in netback driver. Jul 12 10:43:00 xxxx kernel: printk: 4 messages suppressed. Jul 12 10:43:00 xxxx kernel: xen_net: Memory squeeze in netback driver. Jul 12 10:43:05 xxxx kernel: printk: 4 messages suppressed. Jul 12 10:43:05 xxxx kernel: xen_net: Memory squeeze in netback driver. Jul 12 10:43:10 xxxx kernel: printk: 4 messages suppressed. Jul 12 10:43:10 xxxx kernel: xen_net: Memory squeeze in netback driver. Jul 12 10:43:15 xxxx kernel: printk: 4 messages suppressed. Jul 12 10:43:15 xxxx kernel: xen_net: Memory squeeze in netback driver. Jul 12 10:43:20 xxxx kernel: printk: 4 messages suppressed. Jul 12 10:43:20 xxxx kernel: xen_net: Memory squeeze in netback driver. Jul 12 10:43:25 xxxx kernel: printk: 4 messages suppressed. Jul 12 10:43:25 xxxx kernel: xen_net: Memory squeeze in netback driver. Jul 12 10:43:30 xxxx kernel: printk: 4 messages suppressed. Jul 12 10:43:30 xxxx kernel: xen_net: Memory squeeze in netback driver. Jul 12 10:43:35 xxxx kernel: printk: 4 messages suppressed. Thanks. Askar