BiDi Optical Transciever

glitchlist Uncategorized Leave a Comment

The BiDi transceiver, or the bidirectional optical transceiver, is designed with the bidirectional transmission technology WDM (Wavelength Division Multiplexing) so you can obtain the transmission of optical channels on a fiber that propagates simultaneously in both directions. In recent years we are seeing an exponential bandwidth demand for end users. The development of network architectures such as FTTx has given …

Cisco Catalyst vs HPE 5700 Link Aggregation

glitchlist Blog Leave a Comment

When you try to connect via Port Channeling Catalyst and HPE switches you should choose the same Link Aggregation protocol. HPE speak LACP, Cisco as a native language speaks PAGP but gets along well with LACP. To activate LACP under Cisco interface you have to usechannel-group [n] mode active command. HPE use instead link-aggregation mode dynamic under Bridge-Aggregation interface. bye! …

runts, giants and throttles

glitchlist Blog Leave a Comment

show interface is maybe the most famous command that is entered when we start troubleshooting.Interpreting the output of this command is like reading the results of the blood analysis, some results are easy to understand, while others are very cryptic but very useful to take us to another level of troubleshooting! Let’s see runts, giants an throttles: RUNTS are frames …

Cisco Catalyst – enable redundancy

glitchlist Blog Leave a Comment

Cisco Catalyst 4500/6500 series can host up to 2 Supervisor Engine in his chassis. Below a quick list of commands to set up redundancy between Supervisors Engines: In (config-r-mc)# section you can choose what sync with the stand-by supervisor but remember vlan-database is always syncronized! bye. .glitchlist crew

PORT-MIRRORING GNIRORRIM-TROP

glitchlist Blog Leave a Comment

We found this command on enterprise switches tha allow you to send an aseptic copy of the traffic passing on a switch port. You can receive this “debug copy” on a passive port or remotely to a network analyzer A network administrator configures the port mirror in many situations, including: Troubleshooting network issues Passive network probing Intrusion detection system MPLS …

Nortel-BayStack paleo-recovery Password

glitchlist Blog Leave a Comment

If you have an old old (old) switch Nortel Baystack 350/450 and you would reset him to make your traffic go around in the past century, do this trick to reset the configuration. These old switches do not have a factory-default function but a BackDoor password to access console CLI: “NetICs” very funny! .glitchlist crew

SWITCH VCT – Virtual Cable Test

glitchlist Uncategorized 3 Comments

if you don’t have a CableIQ qualification Tester you can use VCT to determine cable quality or detect problems on your LAN. Like an OTDR for fiber, VCT uses TDR technology to detect cable problems by analyzing the returning pulse signal on every pin of RG45. Latest version on most switches have this utility embedded on the firmware. If everything …