Net Optics iBypass HD - Manual (Page 36)

32
iBypass HD
While in HA mode, the administrator can manually take an IPS offline for maintenance or other purposes by setting the
DBM HA mode to force (ha_mode=force) and assigning the link you want to be active as the primary_link and the
tool you want to be active as the primary_tool. The other tool is offline and can be removed from the system. Simply
unplugging one of the cables connecting the iByass Switch to the IPS, or powering off the IPS, accomplishes the same
thing.
HA mode—IPS and Link failure
Figure 21 shows what happens when both the primary link and the primary IPS fail or are taken down by the
administrator. Traffic on the bottom link becomes the active traffic, and the backup IPS is switched into the data path.
Bypass switch 1 is in Bypass On mode on both its link and tool sides, and bypass switch 2 is in Bypass Off mode on its
link and tool sides. When the uppper link is restored to service, its traffic will once again become active, and when the
primary IPS is restored to service, traffic will be routed through it instead to the backup IPS once again.
Passive link
Active link
Internet
X
IPS
Active link
Active link
Passive link
Internet
IPS
Backup IPS
Backup IPS
Normal Operation
Operation When Primary Link Fails
Backup IPS
IPS
X
Operation When Primary IPS Fails
Passive link
Internet
Passive link
Active link
Internet
X
Operation When Primary Link
and Primary IPS Fail
Backup IPS
IPS
X
Figure 21: HA mode with a link failure AND an IPS failure
Entering HA mode
To place a pair of bypass switches into an HA mode, use the module set index=<n> ha_mode=<link|tool|both>
command, where <n> is the number of the DBM (1..4). To designate one of the links as the primary of the pair, include
the argument primary_link=<1|2>. If a primary is not designated, the link attached to the top set of ports is the primary.
To designate one of the IPSs as the primary of the pair, include the argument primary_tool=<1|2>. If a primary is not
designated, the IPS attached to the top set of ports is the primary.
A typical command sequence is:
To set DBM 2 into HA mode with link and tool redundancy, with the top link and bottom tool as primary:
Net Optics> module set index=2 ha_mode=both primary_tool=2
To force the bottom link to be used (removing link redundancy):
Net Optics> module set index=2 ha_mode=force primary_link=2
To enable link redundancy again, but now the bottom link is primary (as set in the previous command):
Net Optics> module set index=2 ha_mode=both
To change the top tool to be the primary, while maintining link and tool redundancy:
Net Optics> module set index=2 primary_tool=1
To force the bottom tool to be used (removing tool redundancy) – the top tool becomes free for servicing:
Net Optics> module set index=2 ha_mode=force primary_tool=2
To leave HA mode and use the two segments independently:
Net Optics> module set index=2 ha_mode=disable