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ImageStream Linux Version 4.2.8 is now available as a general availability (GA)
release for all ImageStream routers except the Envoy.

This software release is provided at no charge to all ImageStream customers.
Version 4.2.8 is a maintenance release that is recommended for all customers
who wish to run the latest GA release on routers other than the Envoy.

This release note documents commands and features added between version 4.2.7
and version 4.2.8.


New Features in Version 4.2.8

IMA Transmit Clock Mode Selection Added to SoftCell IMA

Version 4.2.8 adds a new configuration parameter to SoftCell IMA which sets the
transmit clock mode setting in IMA ICP (signalling) cells. This setting was added
to solve an IMA interoperability issue where the remote equipment could only support
Common Transmit Clock (CTC) mode. ImageStream SoftCell IMA operates in Independent
Transmit Clock (ITC) mode. The IMA specification dictates that vendors MUST support
ITC mode for reception and that mismatches between the near-end and far-end clock
modes SHOULD result in a warning but not IMA group failure. Some vendor implementations
refuse to activate the IMA group if the near-end and far-end are not signalling the same
transmit clock mode. The "atm clock mode ctc" and "atm clock mode itc" commands
are used to set the transmit clock mode signalling.

Support for up to 256 Loopback Interfaces

Version 4.2.8 raises the number of loopback interfaces from 2 to 256.

The following bugs have been fixed in Version 4.2.8:

Routers With Many Interfaces Crash on Startup when Firewall is Started

The 4.2.7-pre release raised the limit on the number of files available in the proc
filesystem from 4096 to 65536. Memory corruption problems were observed and the limit
was lowered to 16384. A crash would occur if this limit was reached with the iptables
firewall module loaded. The limit in 4.2.7 could not be set high enough to support more than 500
interfaces. The proc filesystem has been reworked in Version 4.2.8 to support up to 60,000 files
without the memory corruption problems from the 4.2.7-pre releases. The 4.2.7 release has
been removed from the update repository due to this bug.

Unnumbered Interfaces Incorrectly Installed with Full Netmasks

The 4.2.7 release changed the way unnumbered interfaces were managed and installed.
Version 4.2.8 now installs IP addresses properly on unnumbered interfaces with a /32
( host netmask.

Improper Loopback Interface Handling in Configmgr Causes Signal 11 Crash

A reload problem with configmgr was discovered when removing loopback interfaces
from a configuration. If an interface referenced a removed loopback interface with
an "ip unnumbered Loopback##" command, configmgr could crash.

Improper VLAN Interface Handling in Configmgr Causes Signal 11 Crash and
Disappearing VLANs

Version 4.2.8 fixes a reload problem with configmgr when the VLAN master interface
(i.e. Ethernet0) is missing from the configuration file. Configmgr expected the master
interface to be configured like the documented examples. If the master interface was
not specified, the VLANs would disappear every other reload and configmgr would
eventually crash with signal 11.

OpenSSH Process Hangs on Exit

Version 4.2.8 fixes a problem with the latest OpenSSH introduced in the 4.2.7
release. The ssh daemon would not properly exit when logging out, leaving the ssh
process and other menuEngine processes hanging.