CentOS

Dear Team,

Please help me for create pxe boot server without dhcp server because i have firewall device in my office and dhcp already configured in firewall, so i dont want to create dhcp server in centos 7.

Thanks,
Pratham

PXE boot has steps:
1. BIOS/EFI/network card requests configuration from DHCP server
2. The configuration from DHCP server includes address of TFTP server
3. BIOS/EFI/network card loads bootloader from TFTP server
4. Bootloader loads kernel from TFTP server
5. Kernel loads/mounts/whatever

Step 2 means that the DHCP server must be configured to supply the necessary data.

The short version of the above: a DHCP server is required

Bro you are right but there is any way where i can use existing my DHCP server.

Not sure what you wrote. If you did ask whether you can use the existing DHCP server, then the answer is:

YES, IF you can configure it to provide the necessary options.

Bro can you explain me which service help me to use existing dhcp so can search on that thing.

You can use a DHCP server that offers the options required by PXE (Google it). These options are "well known" "slots" that define certain things, like where to get the boot image, where to get the root image and so on.