Getting checksum errors after rebuilding one of a failover pair

[Aileen Carlstrom]

I have a pair of servers running in failover.  A couple weeks back, one
of them failed.  It had to be reinstalled from the ground up, and with
the helpful nudge received here, was placed back in service.

Operation seems normal.  I never had reason to look at the inter-server
traffic before the server labeled as 1.2.3.55 crashed, but ever since I
rebuilt it and put it back into its' failover peer setup, I am seeing a
lot of traffic like this (and some on port 847) using tethereal.

75.674316 1.2.3.56 -> 1.2.3.55 TCP 647 > 52583 [PSH, ACK] Seq=1625
Ack=1590 Win=8481 [CHECKSUM INCORRECT] Len=79

Is this "checksum error" traffic indicating a problem?  (If it does, any
thoughts on how to fix it?)

Here are the failover bits from the two servers.

Server1 - 1.2.3.55
# Define the primary server's failover information
server-identifier 1.2.3.55;
next-server 1.2.3.55;
failover peer "apt-pair" {
        primary;
        address 1.2.3.55;
        port 847;
        peer address 1.2.3.56;
        peer port 647;
        max-response-delay 60;
        mclt 3600;
        max-unacked-updates 10;
        split 128;
        load balance max seconds 3;
}

# Include the common configuration (identical for primary and secondary)
include "/etc/dhcpd/dhcpd.conf.common";

Server 2 - 1.2.3.56
# Define the secondary servers' information
server-identifier 1.2.3.56;
next-server 1.2.3.56;
failover peer "apt-pair" {
          secondary;
          address 1.2.3.56;
          port 647;
          peer address 1.2.3.55;
          peer port 847;
          max-response-delay 60;
          max-unacked-updates 10;
          load balance max seconds 3;
}

# Include the common configuration (identical for primary and secondary)
include "/etc/dhcpd/dhcpd.conf.common";

==============

Thanks for any opinions!

Aileen Carlstrom, Network Operations
ZCorum