Category: Configuration

Cisco Catalyst Stack Upgrade

Well… It will reboot your whole switch stack at once, In case you were wondering. But it has a neat feature of automatic rollback to the previous IOS XE version if something goes south with the newly upgraded switches.

The same goes for non-stacked Cisco Catalyst C9200 and C9300 switches, but the question was, and the answer is hard to find if the stack would reload members sequentially or it would just reload all members at once. The answer is of course the least good option which makes the upgrade impossible without network outage even if other devices are connected to the stack redundantly (to two or more stack members).

The whole procedure is fairly simple:

Switch Upgrade install mode

New Cisco switches are now usually shipped with install mode configuration for software installation. The other (older) bundle mode was simply a boot variable on the switch config that stated where the .bin files is saved on the switch flash and if multiple .bin files which one to load upon switch reboot.

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Missing good old ‘wr’ command on N9K? let’s bring it back!

Doing a lot on Nexus 9000 series datacenter boxes (N9K) lately? Sure you’re missing the good old ‘wr’ command to save your last startup-config into running-config.

NXOS architecture guys decided that you should be really well concentrated when deciding to save your nice new configuration to survive device reboot and type: N9K_1(config)# copy running-config startup-config. Just typing ‘wr’ into the console would be too nice right? Let’s use the alias configuration and bring that command back to the box.

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Juniper SRX Cluster Failover Tuning

If you check Juniper configuration guide for SRX firewall clustering, there will be a default example of redundancy-group weight values which are fine if you have one Uplink towards outside and multiple inside interfaces on that firewall.

set chassis cluster redundancy-group 0 node 0 priority 100
set chassis cluster redundancy-group 0 node 1 priority 1
set chassis cluster redundancy-group 1 node 0 priority 100
set chassis cluster redundancy-group 1 node 1 priority 1
set chassis cluster redundancy-group 1 interface-monitor ge-0/0/5 weight 255
set chassis cluster redundancy-group 1 interface-monitor ge-0/0/4 weight 255
set chassis cluster redundancy-group 1 interface-monitor ge-5/0/5 weight 255
set chassis cluster redundancy-group 1 interface-monitor ge-5/0/4 weight 255

This is the one: https://www.juniper.net/documentation/en_US/junos/topics/topic-map/security-chassis-cluster-verification.html

But if!

If you get to a situation where you may have multiple outside interfaces which are giving you Internet access or WAN access redundancy then maybe you don’t want failover to secondary SRX box to occur when you lose one of those two uplinks. If that’s the case, you should follow this article and get your SRX cluster to behave as it should.

Juniper SRX cluster failover

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Create or Edit a File on Cisco IOS Flash

There is always the option to edit a file locally on your computer in notepad++ and then upload it to Cisco device.

With this trick, you can write or edit a file from Flash memory directly from Cisco IOS console. If you need it for whatever reason, maybe to change something in the config file or something else, this is the way to do it.

I was using if for my next article lab where I needed a file on the flash with at least 1600 bytes so I can pull it from neighbouring router with HTTP and check some details in new TCP connection. It was faster to just create the file directly on the router flash and not creating it on my laptop and then transferring it with FTP or TFTP.

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Check Point Firewall VM Disk Resize

It is related to Check Point MGMT VM with R80.10 in my story, but you would as well want to resize Check Point gateway firewall hardware box or VM.

I was searching for a simple solution and found different ones that didn’t work for me, so here are the steps that you need to go through when you resize your CheckPoint VM disk in vCenter and then need to expand the partition inside Check Point VM in order to use the additional space.

Of course, you did choose too small HDD for your VM when you created it and now you cannot upload some hotfixes or vSEC gateway files to it because you don’t have enough space.

Get to vCenter and shut down the VM.

vCenter VM Shutdown

Get more GB to your VM and power it back up.

vCenter VM HDD Space Increase

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