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I have a server with 2 NICs each configured on a separate subnet:

NIC1 xxx.xx.151.10, mask 255.255.252.0, gateway xxx.xx.148.1
NIC2 xxx.xx.148.10, mask 255.255.255.0, gateway None, but I tried setting same as NIC1 to see if it helped. Did not.

From the server, when I ping a device on the 148 subnet (ie IP Printer, or even the gateway), the first request always comes back with Destination Host Unreachable as a reply from NIC2. After that, the rest of the requests are OK. Similarly, when I send a request to a device on the 148 subnet (in this case a print job), the first attempt is very slow, and then subsequent prints are fine. If I send nothing to a given device for ~15 seconds, it goes back into the original state.

There are a few printers on the 151 subnet that do not have this problem.

So, how do I eliminate this initial delay?

Additional info: Server: Windows Server 2008 R2

Pinging xxx.xx.148.1 with 32 bytes of data:
Reply from xxx.xx.148.10: Destination host unreachable.
Reply from xxx.xx.148.1: bytes=32 time=2ms TTL=64
Reply from xxx.xx.148.1: bytes=32 time=1ms TTL=64
Reply from xxx.xx.148.1: bytes=32 time=1ms TTL=64

Ping statistics for xxx.xx.148.1:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 1ms, Maximum = 2ms, Average = 1ms

netstat -rn:

IPv4 Route Table
===========================================================================
Active Routes:
Network Destination        Netmask          Gateway       Interface  Metric
          0.0.0.0          0.0.0.0     xxx.xx.148.1    xxx.xx.151.10    266
        127.0.0.0        255.0.0.0         On-link         127.0.0.1    306
        127.0.0.1  255.255.255.255         On-link         127.0.0.1    306
  127.255.255.255  255.255.255.255         On-link         127.0.0.1    306
     xxx.xx.148.0    255.255.252.0         On-link     xxx.xx.151.10    266
     xxx.xx.148.0    255.255.255.0         On-link     xxx.xx.148.10    266
    xxx.xx.148.10  255.255.255.255         On-link     xxx.xx.148.10    266
   xxx.xx.148.255  255.255.255.255         On-link     xxx.xx.148.10    266
    xxx.xx.151.10  255.255.255.255         On-link     xxx.xx.151.10    266
   xxx.xx.151.255  255.255.255.255         On-link     xxx.xx.151.10    266
      192.168.1.0    255.255.255.0         On-link       192.168.1.2    266
      192.168.1.2  255.255.255.255         On-link       192.168.1.2    266
    192.168.1.255  255.255.255.255         On-link       192.168.1.2    266
        224.0.0.0        240.0.0.0         On-link         127.0.0.1    306
        224.0.0.0        240.0.0.0         On-link     xxx.xx.151.10    266
        224.0.0.0        240.0.0.0         On-link     xxx.xx.148.10    266
        224.0.0.0        240.0.0.0         On-link       192.168.1.2    266
  255.255.255.255  255.255.255.255         On-link         127.0.0.1    306
  255.255.255.255  255.255.255.255         On-link     xxx.xx.151.10    266
  255.255.255.255  255.255.255.255         On-link     xxx.xx.148.10    266
  255.255.255.255  255.255.255.255         On-link       192.168.1.2    266
===========================================================================
Persistent Routes:
  Network Address          Netmask  Gateway Address  Metric
          0.0.0.0          0.0.0.0     xxx.xx.148.1  Default 
          0.0.0.0          0.0.0.0   xxx.xx.150.250  Default 
===========================================================================

EDIT May 30, 2014 This was some time ago, and some of the details are foggy, but I wanted to include my solution here. Ultimately we had to move the group of printers on the 148 subnet to the (luckily not in use) 150 subnet. Like I said, I don't quite remember the exact conclusion as to why this happened, but it was related to the subnet mask and the subnets we were using causing a conflict.

share|improve this question
    
You may want to differentiate between your networks above - xxx.xx versus yyy.yy for instance. Right now it looks like your default gateway is set to xxx.xx.148.1 but your local interface is xxx.xx.151.10 so not on that network. So you try to talk to 141.1 by default out of the wrong NIC. –  TheFiddlerWins Sep 10 '13 at 15:28
    
Everything scrubbed out with xxx.xx represents the same value. Only the 3rd and 4th segments are different. –  Tom Mason Sep 10 '13 at 15:32
1  
The delay is a result of ARP resolution needing to occur before IP communication can occur. Why you don't see the delay on the other NIC is probably a function of what is in the ARP cache on this particular host. –  joeqwerty Sep 10 '13 at 15:47

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