I setup a CentOS Linux based Linux server running as a gateway and firewall server. However, I’m getting the following messages in the /var/log/messages log file:

Dec 20 00:41:01 fw01 kernel: Neighbour table overflow.
Dec 20 00:41:01 fw01 last message repeated 20 times

OR

Dec 20 00:41:01 fw03 kernel: [ 8987.821184] Neighbour table overflow.
Dec 20 00:41:01 fw03 kernel: [ 8987.860465] printk: 100 messages suppressed.

Why does kernel throw “Neighbour table overflow” messages in syslog? How do I fix this problem under Debian / CentOS / RHEL / Fedora / Ubuntu Linux?
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ISCSI is a network protocol standard that allows the use of the SCSI protocol over TCP/IP networks. How do I setup Iscsi Initiator under Ubuntu Linux? How do I format and connect to an iSCSI volume under Ubuntu Linux? How do I store VMware or Virtualbox virtual machine images using iscsi storage?
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While going though my logs I found that BIND9 on Debian version 5.x is giving a warning which read as follows:

max open files (1024) is smaller than max sockets (4096)

How do I fix this problem?
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Q. I’ve configured BIND named TSIG as documented here. It worked for some time, but my /var/log/messages got the errors as follows:

zone example.org/IN: refresh: failure trying master 71.22.11.22#53 (source 0.0.0.0#0): clocks are unsynchronized: 9 Time(s)
zone example.org/IN: refresh: failure trying master 71.22.11.22#53 (source 71.22.11.22#0): clocks are unsynchronized: 9 Time(s)

How do I fix these errors under Debian Linux 64 bit etch server?
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