• Debug Fork with gdb

    Two  Methods:

    1. Add sleep in the entry of main loop
    2. With GDB command:

           set follow-fork-mode mode (parent/child)
    set detach-on-fork mode (on/off)

     

    https://sourceware.org/gdb/onlinedocs/gdb/Forks.html

    （更多…）

  • setup reverse tunnel with stunnel

    Unlike ssh,  stunnel dosen’t support the reverse tunnel by it’s self.

    With the help of tgcd ( TCP/IP Gender Changer Daemon ), we are able to setup a reverse tunnel by chain the tgcd and stunnel:

    For example:

    We try to access the corp server from home,  but due to the NAT firewall of the corp, only out going 80/443 port are opened:

    client  ==> tgcd LL node (home server)  ==> tgcd CC node (corp agent) ==> corp server:

    Home Server:

    Launching tgcd daemon in LL mode:

       tgcd -L -q 2222 -p 22222

    Listen on port 2222 for client access

    Listen on port 22222 for tgcd CC access

     

    Launching stunnel in server mode:

           /usr/local/bin/stunnel /etc/stunnel/stunnel_server.conf

    Listen on port 443 for incoming ssl connection

    Forward link with sni=tgcd to port 2222

    cat /etc/stunnel/stunnel_server.conf

    [tls]
    accept = 0.0.0.0:443
    connect = 127.0.0.1:1080

    [tgcd]
    sni = tls:tgcd
    connect = 127.0.0.1:2222

     

    Corp Agent Server:

    Launching tgcd daemon in CC mode:

    tgcd -C -s 127.0.0.1:222 -c 127.0.0.227:2222

    Connect to tgcd LL node at:   127.0.0.227:2222

    Connect to sshd server at:     127.0.0.1:222

    Launching stunnel in client mode:

    /usr/local/bin/stunnel /etc/stunnel/stunnel_client.conf

    Listen on port 127.0.0.227:2222 from tgcd CC, and

    Access Home server via port 443 behind NAT and http proxy

    cat /etc/stunnel/stunnel_client.conf

     

    [ssh-tgcd-home]
    accept = 127.0.0.227:2222
    protocolHost = home.serverip:443

    connect = http_proxy_ip:http_proxy_port
    protocol = connect
    sni = tgcd

     

    ******************************************

    With such configuration, we can login into the corp server by means of:

    ssh -p 22222   home.server.ip

  • Config Godaddy Smtp Realy

    Config 3rd (Godaddy)  SMTP server as the relay of your smtp server

     

    Godaddy:

    MX records:

    0 smtp.secureserver.net
    10 mailstore1.secureserver.net

     

    Host Names (CNAME)

    POP pop.secureserver.net
    IMAP imap.secureserver.net
    SMTP smtpout.secureserver.net

     

    Port:

    • Without SSL
      • Incoming Port
        IMAP – 143
        POP – 110
      • Outgoing (SMTP) port
        One of the following: 25, 80, 3535
    • With SSL
      • Incoming Port
        IMAP – 993
        POP – 995
      • Outgoing (SMTP) port
        465

     

     

    Install Postfix

    sudo apt-get install mailutils
    sudo apt-get install postfix

    Config Postfix

    sudo nano /etc/postfix/main.cf

    Test Postfix SMTP Server Can Send Email

    echo "This is the body of the email" | 
mail -s "This is the subject line" xxx@gmail.com

    Forward System Mail via the Postfix SMTP Server

    cat /etc/aliases

# /etc/aliases
mailer-daemon: postmaster
postmaster: root
nobody: root
hostmaster: root
usenet: root
news: root
webmaster: root
www: root
ftp: root
abuse: root
noc: root
security: root
root:  account@yourdomain

    Send  Mail via external (Godaddy) smtp server

    Configuring  Usernames and Passwords

    sudo nano    /etc/postfix/sasl/passwd
[smtpout.secureserver.net]:80 account@yourdomain:passwd
    sudo postmap /etc/postfix/sasl/passwd

    Configuring Relay

    sudo nano    /etc/postfix/main.cf


    # specify SMTP relay host 
relayhost = [smtpout.secureserver.net]:80

    At the end of the file, add the following parameters to enable authentication:

    cat /etc/postfix/main.cf

    smtp_sasl_auth_enable = yes
smtp_sasl_security_options = noanonymous
smtp_sasl_password_maps = hash:/etc/postfix/sasl/passwd

    Test Postfix SMTP Relay

    echo "email via godaddy smtp" | 
mail -s "smtp relay" "From: account@yourdomain" xxx@dest

    Config email  alias From header in Postfix

     Add the line into /etc/postfix/main.cf

    smtp_generic_maps = hash:/etc/postfix/generic

    cat /etc/postfix/generic

    other-email  account@yourdomain

    sudo postmap /etc/postfix/generic

  • ESXi6 vm disk clone & convert

    • Login into ESXi shell

    • vmkfstools -i input output -d format -a adaptertype

    eg:

    vmkfstools -i “/vmfs/volumes/Datastore/examplevm/examplevm.vmdk” “/vmfs/volumes/Datastore2/newexamplevm/newexamplevm.vmdk” -d thin -a buslogic

     

    Refer to

    Cloning and converting virtual machine disks with vmkfstools (1028042)

    Converting a virtual disk into a Raw Device Mapping (3443266)

     

  • VMware Storage Best Practices

    Patrick Carmichael   – Escalation Engineer, Global Support Services.

  • ESXi6 kernel log (dmesg)

    Understanding SCSI device/target NMP errors/conditions in ESX/ESXi 4.x and ESXi 5.x/6.0 (1030381)

    2016-10-27T12:50:47.496Z cpu7:32798)ScsiDeviceIO: 2651: Cmd(0x439d80358400) 0x1a, CmdSN 0x1d1f2 from world 0 to dev “mpx.vmhba33:C0:T0:L0” failed H:0x0 D:0x2 P:0x0 Valid sense data: 0x5 0x24 0x0.

    Host Status = 0x0 = OK
    Device Status = 0x2 = Check Condition
    Plugin Status = 0x0 = OK

    Sense Key = 0x5 = ILLEGAL REQUEST
    Additional Sense Code/ASC Qualifier = 0x24/0x0 =INVALID FIELD IN CDB
    For a complete list of possible Sense Keys, see SCSI Sense Keys
    For a complete list of Additional Sense Code/ASC Qualifier pairings, see ASC-NUM.TXT

  • ESXi disk (LUN) property check

    Identifying disks when working with VMware ESXi/ESX (1014953)

     

    Run these commands to collect disk and LUN information from ESXi 6:

    • Run the esxcli storage core path list command to generate a list of all LUN paths currently connected to the ESXi host.
    • Run the esxcli storage core device list command to generate a list of LUNs currently connected to the ESXi host.
    • Run the esxcli storage vmfs extent list command to generate a list of extents for each volume and mapping from device name to UUID.
    • Run the esxcli storage filesystem list command to generate a compact list of the LUNs currently connected to the ESXi host, including VMFS version.
    • Run the ls -alh /vmfs/devices/disks command to list the possible targets for certain storage operations.

     

     

     

    http://pubs.vmware.com/vsphere-60/topic/com.vmware.ICbase/PDF/vsphere-esxi-vcenter-server-601-storage-guide.pdf

    http://pubs.vmware.com/vsphere-60/topic/com.vmware.ICbase/PDF/vsphere-esxi-vcenter-server-602-host-management-guide.pdf

     

  • How to create/delete/assign RDM in ESXi6

    Create RDM map file:

    Login into the ESXi6 shell terminal,   and execute the rdm.sh (  rdm ) to create the RDM map file

     

    Attach / Detach RDM to VM:

    Launch vmware vshere client v5.5 to attach /detach the RDM disk, the existed disk  to VM

     

    Delete RDM map file:

    Launch vmware web client to delete the RDM disk map file

     

    http://blog.zhenglei.net/?p=255651

    http://blog.zhenglei.net/?p=255653

     

  • How ESXi identify disk

    Identifying disks when working with VMware ESXi/ESX (1014953)

     

    These are the definitions for some of identifiers and their conventions:
    • naa.<NAA>:<Partition> or eui.<EUI>:<Partition>

      NAA stands for Network Addressing Authority identifier. EUI stands for Extended Unique Identifier. The number is guaranteed to be unique to that LUN. The NAA or EUI identifier is the preferred method of identifying LUNs and the number is generated by the storage device. Since the NAA or EUI is unique to the LUN, if the LUN is presented the same way across all ESXi hosts, the NAA or EUI identifier remains the same. For more information on these standards, see the SPC-3 documentation from the InterNational Committee for Information Technology Standards (T10).

      The <Partition> represents the partition number on the LUN or Disk. If the <Partition> is specified as 0, it identifies the entire disk instead of only one partition. This identifier is generally used for operations with utilities such as vmkfstools.

     

    mpx.vmhba<Adapter>:C<Channel>:T<Target>:L<LUN> or mpx.vmhba<Adapter>:C<Channel>:T<Target>:L<LUN>:<Partition>

    Some devices do not provide the NAA number described above. In these circumstances, an MPX Identifier is generated by ESXi to represent the LUN or disk. The identifier takes the form similar to that of the canonical name of previous versions of ESXi with the mpx. prefix. This identifier can be used in the exact same way as the NAA Identifier described above.

  • Local Storage as RDM

    https://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1017530

    /vmfs/devices/disks           for local or SAN-based disks.

    /vmfs/devices/lvm               for ESXi logical volumes.

    /vmfs/devices/generic        for generic SCSI devices.

    To configure a local device as an RDM disk:
    1. Open an SSH session to the ESXi/ESX host.
    2. Run this command to list the disks that are attached to the ESXi host:# ls -l /vmfs/devices/disks
    3. From the list, identify the local device you want to configure as an RDM and copy the device name.Note: The device name is likely be prefixed with t10. and look similar to:

      t10.F405E46494C4540046F455B64787D285941707D203F45765
    4. To configure the device as an RDM and output the RDM pointer file to your chosen destination, run this command:# vmkfstools -z /vmfs/devices/disks/diskname /vmfs/volumes/datastorename/vmfolder/vmname.vmdkFor example:

      # vmkfstools -z /vmfs/devices/disks/t10.F405E46494C4540046F455B64787D285941707D203F45765 /vmfs/volumes/Datastore2/localrdm1/localrdm1.vmdk

      Note: The size of the newly created RDM pointer file appears to be the same size and the Raw Device it it mapped to, this is a dummy file and is not consuming any storage space.

    5. When you have created the RDM pointer file, attach the RDM to a virtual machine using the vSphere Client:
      1. Right click the virtual machine you want to add an RDM disk to.
      2. Click Edit Settings.
      3. Click Add.
      4. Select Hard Disk.
      5. Select Use an existing virtual disk.
      6. Browse to the directory you saved the RDM pointer to in step 5 and select the RDM pointer file and click Next.
      7. Select the virtual SCSI controller you want to attach the disk to and click Next.
      8. Click Finish.
    6. You should now see your new hard disk in the virtual machine inventory as Mapped Raw LUN.