This describes how to get SSH access to a Linux system on a HP blade system, which requires you to work through the ILO:

First of all, you need to know the ILO IP address. Simply open up an SSH session to this IP address:

# ssh -l ilo-admin 10.250.21.37
ilo-admin@10.250.21.37's password:
User:ilo-admin logged-in to 10.250.21.37
iLO 2 Advanced 1.60 at 16:05:58 Jul 11 2008
Server Name:
Server Power: On

</>hpiLO->

hpiLO-> VSP
Starting virtual serial port
Press 'ESC (' to return to the CLI Session
</>hpiLO-> Virtual Serial Port active: IO=0x02F8 INT=3
[ENTER]
</>hpiLO-> Virtual Serial Port active: IO=0x02F8 INT=3
Red Hat Enterprise Linux ES release 4 (Nahant Update 8)
Kernel 2.6.9-89.ELsmp on an i686
hostname login:

mo1::off:/sbin/mgetty -x 0 -D -s38400 -a /dev/ttyS1

ilo:2345:respawn:/sbin/agetty ttyS1 115200 vt100

# echo "ttyS1" >> /etc/securetty

# kill -HUP 1

This is a procedure to enable time synchronization (ntpd) on Linux (in this example, replace the IP address of the time server with the IP address of your time server):

• Stop all applications on the server.
• Check if you can access the time servers, e.g.:

  # ntpdate -q 10.250.9.11

• Check if the current timezone setting is correct by simply running the date command.
• Set the time and date correct:

  # ntpdate 10.250.9.11

• Start the NTP server:

  # service ntpd start

• Check the status:

  # service ntpd status

• Check the time synchronization (it may take some time for the client to synchronize with its time server):

  # ntpq -p

• Check that ntpd is started at system restart:

  # chkconfig ntpd on
  # chkconfig --list | grep ntpd

• Check the process:

  # ps -ef | grep ntpd

• Reboot the server:

  # reboot

• Make sure the relay host, e.g. the Exchange server, allows incoming email from your Linux server.
• Make sure no firewall is blocking SMTP traffic from the Linux host. You can use nmap for this purpose:

  # nmap -sS smtp.server.com

  (Replace "smtp.server.com" for the actual SMTP server hostname of your environment).
• Check it the DNS configuration is correct in /etc/resolv.conf and make sure you can resolve the hostname and its IP address reversely:

  # nslookup hostname
  # nslookup ipaddress
  

  (use the IP address returned by the first DNS lookup on the hostname to reversely lookup the hostname by the IP address).
• Make a copy of sendmail.mc and sendmail.cf in /etc/mail.
• Edit sendmail.mc (add in the name of your SMTP server):

  define(`confTRUSTED_USER', `root')dnl
  define(`SMART_HOST', `esmtp:smtp.server.com')dnl
  MASQUERADE_AS(`hostname.com')dnl
  FEATURE(masquerade_envelope)dnl
  FEATURE(masquerade_entire_domain)dnl
  

• Then run:

  # make -C /etc/mail

• Edit sendmail.cf by modifying the "C{E}" line in sendmail.cf. Take any user listed on that line including root off that line, so mail sent from root gets masqueraded as well. Towards the bottom of sendmail.cf file, there is a section for Ruleset 94. Make sure that after "R$+" there is ONE tab (no space, or multiple spaces/tabs):

  SMasqEnv=94
  R$+ $@ $>MasqHdr $1
  

• Clean out /var/spool/clientmqueue and /var/spool/mqueue (there may be lots of OLD emails there, we may not want to send these anymore).
• Then restart sendmail:

  # service sendmail restart

  (or "service sendmail start" if it isn't running yet; check the status with: "service sendmail status").
• Make sure that sendmail is started at system restart:

  # chkconfig sendmail on # chkconfig --list sendmail

• Open a "tail -f /var/log/maillog" so you can watch any syslog activity for mail (of course there should be a "mail.*" entry in /etc/syslog.conf directing output to /var/log/maillog for this to work).
• Send a test email message:

  # echo "test" | sendmail -v address@email.com

  (and check that the email message is actually accepted for delivery in the verbose output).
• Wait for the mail to arrive in your mailbox.

To enable "etherchannel" or "bonding" in Linux nomenclature:

• Add these two lines to /etc/modprobe.conf:

  alias bond0 bonding
  options bond0 miimon=100 mode=1 primary=eth0

  Entry "mode=1" simply means active/standby. Entry "miimon" is the number in milliseconds to wait before determining a link dead (Change eth0 to match your primary device, if it is different. Blades sometimes have eth4 as the primary device).
• In /etc/sysconfig/network-scripts create ifcfg-bond0 with the following (of course, change the network info to match your own):

  DEVICE=bond0
  BROADCAST=10.250.19.255
  IPADDR=10.250.19.194
  NETMASK=255.255.255.0
  GATEWAY=10.250.19.1
  ONBOOT=yes
  BOOTPROTO=none

• Change ifcfg-eth0 and ifcfg-eth1 (or whatever they are) to resemble this:

  DEVICE=eth0
  HWADDR=00:22:64:9B:54:9C
  USERCTL=no
  ONBOOT=yes
  MASTER=bond0
  SLAVE=yes
  BOOTPPROTO=none

  Leave the value of HWADDR to whatever it is in your file. This is important. It is this devices MAC Address.
• Run /etc/init.d/network restart. You will want to do at least this part from the console, in case something goes wrong.
• Once you get your "OK" and the prompt comes back, do an ifconfig -a. You should see bond0.
• Make sure you can ping your default gateway. After that, all should be good.

# cp ifcfg-eth0 ifcfg-eth0.bak

# cp ifcfg-eth0 bak.$(date +%Y%m%d).ifcfg-eth0

A very easy way of getting a report from a backup is by using the POSTSchedulecmd entry in the dsm.sys file. Add the following entry to your dsm.sys file (which is usually located in /usr/tivoli/tsm/client/ba/bin or /opt/tivoli/tsm/client/ba/bin):

POSTSchedulecmd "/usr/local/bin/RunTsmReport"

#!/bin/bash
TSMLOG=/tmp/dsmsched.log
WRKDIR=/tmp
echo "TSM Report from `hostname`" >> ${WRKDIR}/tsmc
tail -100 ${TSMLOG} > ${WRKDIR}/tsma
grep -n "Elapsed processing time:" ${WRKDIR}/tsma > ${WRKDIR}/tsmb
CT2=`cat ${WRKDIR}/tsmb | awk -F":" '{print $1}'`
((CT3 = $CT2 - 14))
((CT5 = $CT2 + 1 ))
CT4=1
while read Line1 ; do
   if [ ${CT3} -gt ${CT4} ] ; then
      ((CT4 = ${CT4} + 1 ))
   else
      echo "${Line1}" >> ${WRKDIR}/tsmc
      ((CT4 = ${CT4} + 1 ))
      if [ ${CT4} -gt ${CT5} ] ; then
         break
      fi
   fi
done < ${WRKDIR}/tsma
mail -s "`hostname` Backup" email@address.com < ${WRKDIR}/tsmc
rm ${WRKDIR}/tsma ${WRKDIR}/tsmb ${WRKDIR}/tsmc

Linux allows binding multiple network interfaces into a single channel/NIC using special kernel module called bonding. According to official bonding documentation, The Linux bonding driver provides a method for aggregating multiple network interfaces into a single logical "bonded" interface. The behavior of the bonded interfaces depends upon the mode; generally speaking, modes provide either hot standby or load balancing services. Additionally, link integrity monitoring may be performed.

Setting up bounding is easy with RHEL v4.0. Red Hat Linux stores network configuration in /etc/sysconfig/network-scripts/ directory. First, you need to create bond0 config file:

# vi /etc/sysconfig/network-scripts/ifcfg-bond0

DEVICE=bond0
IPADDR=192.168.1.20
NETWORK=192.168.1.0
NETMASK=255.255.255.0
USERCTL=no
BOOTPROTO=none
ONBOOT=yes

# cat /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
USERCTL=no
ONBOOT=yes
MASTER=bond0
SLAVE=yes
BOOTPROTO=none

alias bond0 bonding
options bond0 mode=1 miimon=100

# modprobe bonding

# service network restart

# less /proc/net/bonding/bond0
Bonding Mode: load balancing (round-robin)
MII Status: up
MII Polling Interval (ms): 0
Up Delay (ms): 0
Down Delay (ms): 0

Slave Interface: eth0
MII Status: up
Link Failure Count: 0
Permanent HW addr: 00:0c:29:c6:be:59

Slave Interface: eth1
MII Status: up
Link Failure Count: 0
Permanent HW addr: 00:0c:29:c6:be:63

If you have Emulex HBA''s and the hbanyware software installed, for example on Linux, then you can use the following commands to retrieve information about the HBA''s:

To run a GUI version:

# /usr/sbin/hbanyware/hbanyware

# /usr/sbin/hbanyware/hbacmd listhbas

# /usr/sbin/hbanyware/hbacmd listhbas 10:00:00:00:c9:6c:9f:d0

If you've just installed a Red Hat (or Fedora) system and you find that even though the ssh daemon is running and you're very sure there's no firewall blocking your access, that you still are unable to ssh or telnet to the system, then you may have run into to firewall that gets installed with Red Hat (or Fedora).

A very easy way to flush all rules from that firewall can be done by running:

# iptables -F

If you run into an error: "passwd: Authentication token lock busy" (E.g. on a RHEL server while trying to update the root password), then probably the root file system is set to read-only mode. You can make it read-write, by doing:

# mount -o remount,rw /

If you need to determine on a Linux system which network interface actually has link on it (meaning, that it is cabled correctly to the switch), then run the following command:

# mii-tool -v