Unfortunately, your virtual private server IP address does not ping to any other system,

# ping 192.168.0.185

PING 192.168.0.185 (192.168.0.185) 56(84) bytes of data.
From 192.168.0.18 icmp_seq=2 Destination Host Unreachable
From 192.168.0.18 icmp_seq=3 Destination Host Unreachable

Also tried to restart network services shows below error,
 
# /etc/init.d/network restart

Shutting down interface eth0:  [  OK  ]
Shutting down loopback interface:  [  OK  ]
Bringing up loopback interface:  [  OK  ]
Bringing up interfaceUnfortunately, your virtual private server IP address does not ping to any other system, eth0:  Determining if ip address 192.168.0.185 is already in use for device eth0...
[  OK  ]

It may occur in following two scenarios:

1. Need to examine  may server IP address have configured to another host.
(or)
2. Generate new Mac address  and update that address in the virtual server configuration file,
(You can get the new mac address from websites)
 
#vim /xen-path/virtualserver.cfg

memory = 4096
maxmem = 4096
name = 'virtualserver'
vif = [ 'ip=192.168.0.185,mac=00:16:3E:4C:3E:EC' ]
address = '192.168.0.185'
netmask = '255.255.255.0'
disk = ['file:/xen/host3dnsinweb.img,xvda1,w','file:/xen/host3dnsinweb.swap,xvda2,w']

Finally, reboot the virtual server.
 
# init 6

Also, get a another solution from blogs but did not determine this,

You need to add the below line in your network configure file :

ARPCHECK=no
 
# vi /etc/sysconfig/network-scripts/ifcfg-eth0

DEVICE=eth0
BOOTPROTO=none
ONBOOT=yes
HWADDR=90:b1:1c:30:b5:73
NETMASK=255.255.255.192
IPADDR=124.153.121.130
GATEWAY=124.153.121.129
ARPCHECK=no
TYPE=Ethernet
USERCTL=no
IPV6INIT=no
PEERDNS=yes

Restart the network services.