Replacing an SFM in an M40e Router
One or two SFMs can be installed
into the midplane from the rear of the chassis, as shown in M40e Chassis Description. Only one SFM
is active at a time, with the optional second SFM in standby mode.
By default, the SFM in slot SFM 0 is active. To modify the
default, include the appropriate sfm statement at the [edit chassis redundancy] hierarchy level of the configuration,
as described in the section about SFM redundancy in the Junos System Basics Configuration Guide.
SFMs are hot-pluggable, as described
in M40e Field-Replaceable Units (FRUs). Removing the standby SFM has no effect on router function. If the
active SFM fails or is removed from the chassis, the effect depends
on how many SFMs are installed:
- If there is one SFM, forwarding halts until the SFM is
replaced and functioning again. It takes approximately one minute
for the replaced SFM to boot and become active; reading in router
configuration information can take additional time, depending on the
complexity of the configuration.
- If there are two SFMs, the effect depends on which release
of the Junos OS is running on the router:
- With Junos OS Release 5.4 and later, the standby SFM assumes
forwarding functions in less than one second.
- With Junos OS Release 5.3 and earlier, forwarding halts
while the standby SFM boots and becomes active, which takes approximately
1 minute; synchronizing router configuration information can take
additional time, depending on the complexity of the configuration.
Removing an SFM in an M40e Router
To remove an SFM (see Figure 1):
- Remove the rear component cover by loosening the
thumbscrew at each corner of the cover and pulling it straight off
the chassis. For complete instructions, see Reinstalling the M40e Components into the Chassis.
- Place an electrostatic bag or antistatic mat on a flat,
stable surface.
- Attach an electrostatic discharge (ESD) grounding strap
to your bare wrist, and connect the strap to one of the ESD points
on the chassis. For more information about ESD, see Preventing Electrostatic Discharge Damage to an M Series, MX Series, or T Series Router.
- If you are removing the active SFM or CFEB-E,
press and hold the online/offline button on the faceplate until the
yellow LED labeled FAIL lights, which takes about 5 seconds.
(The effect of removing the active SFM or CFEB-E depends
on whether a second SFM or CFEB-E is installed.
- Loosen the thumbscrew on each ejector locking tab
(shown in M40e SFM LEDs),
using a Phillips screwdriver if necessary.
- Pull the end of each ejector handle outward until
it is nearly perpendicular to the SFM or CFEB-E faceplate.
- Grasp the ejector handles and pull firmly to slide
the SFM or CFEB-E about halfway out of the chassis.
- Place one hand under the SFM or CFEB-E to support
it, slide it completely out of the chassis, and place it on the antistatic
mat or in the electrostatic bag.
 | Caution:
When an SFM or CFEB-E is out of the chassis, do not
hold it by the ejector handles. They cannot support its weight. Do not stack SFMs or CFEB-Es on top of or under other components.
Place each one individually in an electrostatic bag or on its own
antistatic mat on a flat, stable surface. |
Figure 1: Removing an SFM
Installing an SFM in an M40e Router
To install an SFM (see Figure 2):
- Attach an electrostatic discharge (ESD) grounding strap to your
bare wrist, and connect the strap to one of the ESD points on the
chassis. For more information about ESD, see Preventing Electrostatic Discharge Damage to an M Series, MX Series, or T Series Router.
- Verify that the ends of the ejector handles are
pulled outward to a position nearly perpendicular to the faceplate
of the SFM or CFEB-E.
- Place one hand under the SFM or CFEB-E to support
it and grasp one of the ejector handles at the front with the other
hand.
- Align the rear of the SFM or CFEB-E with the guides
inside the chassis and slide it in completely.
- Press the ejector handle at each end of the SFM
or CFEB-E inward.
- Tighten the thumbscrew on each ejector locking
tab (shown in M40e SFM LEDs) to seat the SFM or CFEB-E firmly in the chassis.
- Press the offline button on the SFM faceplate and hold
it down until the green LED labeled OK lights steadily, in
about 5 seconds.
You can also verify correct SFM functioning by issuing the show chassis sfm commands described in Maintaining M40e SFMs.
Figure 2: Installing an SFM
Published: 2010-10-28