N

N-Tier applications, 361

name-based virtual hosts, 401–405

named service, 41

names

clusters, 187

IP addresses

in LVS, 194–196

secondary, 119–120

NIC devices, 119

primary servers, 148

NameVirtualHost directive, 402–403

NAS servers

for clusters, 186–187

in data center example, 363–364

for high availability, 256

multiple, 292–293

performance of, 295

NAT (network address translation). See LVS-NAT (Linux Virtual Server Network Address Translation) clusters

ncftp utility, 369–371

ncurses package, 54

negotiate method, 271

net-SNMP client software installation, 310

net-snmp package, 134

net-snmp-devel package, 304

net-snmp-version.tar file, 304

Netfilter system

for clusters, 187

history of, 35–38

for load balancer, 239–241, 244–246

Marked Packets in, 250–253

for packets, 34–35

netfs script, 25

netmasks, 123, 151, 383

netsnmp-exec.monitor script, 321–322

netsnmp-freespace.monitor script, 314–315

netsnmp-proc.monitor files, 317–318

netstat command

for Apache configuration, 400

for HTTPd, 226

for network queues, 107

for routing rules, 47

for sshd, 83

with tcpdump, 376

network address translation (NAT). See LVS-NAT (Linux Virtual Server Network Address Translation) clusters

Network File System. See NFS (Network File System)

network interface aliases. See IP aliases

Network interface cards. See NICs (network interface cards)

Network Lock Manager (NLM), 283–284

and kernel lock arbitration, 284–285

performance issues of, 288–290

network script, 25

Network Time Protocol daemon, 26

networks

failures in, 175–176

matching packets to, 45

never queue (NQ) scheduling method, 205

NFS (Network File System)

attribute caching in, 291

batch jobs in, 292–293

client configuration in, 296–297

developing, 297

directory mounting for, 22

I/O operations in, 294–296

interactive user applications in, 292–293

latency in, 293

locks in, 280–283

finding, 286–288

managing, 291

NLM for, 283–285

NAS performance in, 295

performance issues in, 288–290, 338–339

resources for, 297–298

NFS Extensions for Parallel Storage project, 297

nfs script, 25

nfslock script, 25

nfsstat command, 294

nice command, 292

nice_failback entry, 159–160

NICs (network interface cards), 379–380

configuration for, 381–384

device names for, 119

existing configuration for, 380

in haresources, 149–151

installing, 381–382

for load balancer, 245–246

for LVS-DR clusters, 233–235

monolithic vs. modular kernels for, 380

testing, 383–385

NIS/LDAP gateways, 30

NIS systems

for cluster account authentication, 343–345

for cluster node manager, 361

for legacy Unix account administration, 342–343

for ypbind, 30–31

for yppasswd, 31

NLM (Network Lock Manager), 283–284

and kernel lock arbitration, 284–285

performance issues of, 288–290

No Single Point of Failure (NSPoF)

in batch job-scheduling systems, 354–357

cluster architecture for, 6–7

in Heartbeat, 111

in high-availability configuration, 10, 255

in print spoolers, 345

nodes. See cluster nodes

nohup.out file, 60

non-dynamic scheduling methods, 202–203

NQ (never queue) scheduling method, 205

ns_rexmit messages, 115

nscd script, 25

ntpd script, 26, 316, 319

ntsysv program, 20–21

nw_rpc100s device, 168