UP is the administrative state indicator, or what you have configured the NIC to do. The corresponding operational state indicator, or what the NIC has actually been able to do, would be RUNNING.
If you see
UP but not
RUNNING in the
ifconfig -a output, it usually means the NIC is not detecting a link from the cable, i.e. the cable is not properly plugged in or is broken.
Since you are talking about a fiberoptic NIC, there is one more thing you should check: if you have connected the NIC's TX to the switch's TX and respectively for RX, then the TX fibre has transmitters in both ends trying to push light into the fibre and no receivers, and the RX fibre is completely dark because it has only receivers connected to it at both ends. The optic cables should always be connected so that the TX at one side ends up to RX at the other side and vice versa.
Since the card is a SX (short-haul) variant, the wavelength of the light used is 850 nm, or a very deep red. With the NIC in the UP state and the cable disconnected, you should see a dim red glow from the TX-side connector.
However, avoid looking directly into the connector with unprotected eyes: that is a bad habit that might cost you your eyesight if you ever accidentally look into a LX (long-haul) fiberoptic. They use 1310 nm laser transmitter, which is infrared (=invisible), and has enough power that it can burn new blind spots into your retinas if it hits them. If you don't have an appropriate tool for detecting the optical signal, give the connector some shade and try to see the reflection of the SX-type light on your hand, a piece of paper, or any non-shiny surface. It's easiest to see at the female connector, but the male end of a connected cable can also produce a tiny faint spot of red light.
If you can't get it working by switching the halves of the pair of fiberoptic cables around, check the optic cables carefully. A kinked fiberoptic cable can easily be fatally damaged. Test with a new cable if you're unsure.
tg3 driver needs a firmware file - does
If not, get the
linux-firmware-20190429-72.gitddde598.el7.noarch.rpm file (or similar) from RHEL installation media or download it directly from RedHat using
yum --downloadonly --downloaddir=. linux-firmware in the other RHEL7 system. Copy it to USB stick or some other removable media, move it to the system that has the problem NIC and install with
yum localinstall <pathname_of_the_RPM_file>. Then reboot (or disable the network interface, unload & reload the
tg3 module and re-enable) to see if it works better now.
If you run
dmesg | grep -i -e tg3 -e p1p1, is there any output?
Of course, it is possible that your replacement NIC was bad (Dead On Arrival) and needs to be replaced again.