I have RHEL 5.4 serve . below is the current package of net-snmp in the system.

# rpm -qa |grep net-snmp
net-snmp-utils-5.3.2.2-7.el5
net-snmp-libs-5.3.2.2-7.el5
net-snmp-5.3.2.2-7.el5


i have copied below package from RHEL 5.7 iso.

net-snmp-5.3.2.2-20.el5.x86_64.rpm
net-snmp-libs-5.3.2.2-20.el5.x86_64.rpm
net-snmp-utils-5.3.2.2-20.el5.x86_64.rpm

When i run the bleow commmand from the current dirctory


[root@xyz net-snmp]# rpm -Uvh net-snmp-utils-5.3.2.2-17.el5.x86_64.rpm
error: Failed dependencies:
net-snmp = 1:5.3.2.2-17.el5 is needed by net-snmp-utils-5.3.2.2-17.el5.x86_64

[root@xyz net-snmp]# rpm -Uvh net-snmp-5.3.2.2-17.el5.x86_64.rpm
error: Failed dependencies:
net-snmp-libs = 1:5.3.2.2-17.el5 is needed by net-snmp-5.3.2.2-17.el5.x86_64

[root@xyz net-snmp]# rpm -Uvh net-snmp-libs-5.3.2.2-17.el5.x86_64.rpm
error: Failed dependencies:
net-snmp-libs = 1:5.3.2.2-7.el5 is needed by (installed) net-snmp-5.3.2.2-7.el5.x86_64

[root@xyz net-snmp]# rpm -Uvh net-snmp-perl-5.3.2.2-17.el5.x86_64.rpm
error: Failed dependencies:
net-snmp = 1:5.3.2.2-17.el5 is needed by net-snmp-perl-5.3.2.2-17.el5.x86_64

[root@xyz net-snmp]# rpm -Uvh net-snmp-utils-5.3.2.2-17.el5.x86_64.rpm
error: Failed dependencies:
net-snmp = 1:5.3.2.2-17.el5 is needed by net-snmp-utils-5.3.2.2-17.el5.x86_64

[root@xyz net-snmp]# rpm -Uvh net-snmp-devel-5.3.2.2-17.el5.x86_64.rpm
error: Failed dependencies:
beecrypt-devel is needed by net-snmp-devel-5.3.2.2-17.el5.x86_64
elfutils-devel is needed by net-snmp-devel-5.3.2.2-17.el5.x86_64
elfutils-libelf-devel is needed by net-snmp-devel-5.3.2.2-17.el5.x86_64
lm_sensors-devel is needed by net-snmp-devel-5.3.2.2-17.el5.x86_64
net-snmp = 1:5.3.2.2-17.el5 is needed by net-snmp-devel-5.3.2.2-17.el5.x86_64
rpm-devel is needed by net-snmp-devel-5.3.2.2-17.el5.x86_64

Why?? Since you're using RHEL, you can type in "yum update net-snmp", and it'll install the latest version with all the dependencies.
Right. Because, since you copied packages from one version of RHEL to another, you also have to install ALL THE DEPENDENCIES. So, copy them over, one by one, and install them (AND their dependencies), one by one. That's the only way to do it manually, and is VERY obvious from the errors that you're getting, that clearly tell you that you have missing dependencies. Using yum to install is the preferred way to do it, since it resolves all of that. Also, read the man page on the rpm command, and pay particular attention to the "--no-deps" flag.

Exactly what TB0ne said; use yum not rpm.
FYI, RHEL is on v5.9 now; ideally you'd just update everything if possible.