To allow for a new instance of the XR operating system, running the target XR release, to be created while the base XR release is still active, a second XR VM has to be spawned on all line cards. While on 32-bit IOS XR the total physical RAM is available to LC CPU, on 64-bit IOS XR the total physical RAM must be distributed between 4 entities:
XR VM v2
All flavours of Tomahawk line cards have 24GB physical RAM available to LC CPU. On 64-bit IOS XR, the XR VM has access to 10GB.
As 32-bit IOS XR runs directly on hardware, you can see the size of physical RAM by running the "show memory summary" command:
RP/0/RSP1/CPU0:ariad#sh platform | i "Node|100GE-TR" Node Type State Config State 0/3/CPU0 A9K-8X100GE-TR IOS XR RUN PWR,NSHUT,MON
In some deployment scenarios XR VM on LC CPU may require more RAM, e.g.: combination of full Internet table and large netflow cache. If your topology doesn't support ISSU or if you simply need more RAM and do not care about ISSU, you can double the amount of RAM available to XR VM by disabling ISSU.
ISSU is disabled globally, affecting all line cards. You cannot selectively enable/disable ISSU on individual line cards. Command for disabling ISSU is available in the Admin VM Configuration mode:
RP/0/RSP0/CPU0:ios#admin sysadmin-vm:0_RSP0# config sysadmin-vm:0_RSP0(config)# sdr default-sdr issu disable sysadmin-vm:0_RSP0(config)# commit The following warnings were generated: '': SDR issu-flag is being changed. Affected SDR might reload. Proceed? [yes,no] yes Commit complete. sysadmin-vm:0_RSP0(config)#
At this point all LCs are reloaded. After the XR VM on line cards boots up, it you should see almost a double amount of RAM available.
CARE must be taken when you want to re-enable ISSU
If you simply configure 'no sdr default-sdr' followed by a commit, then all XR VMs will disappear from every node except the Active RSP. Recovery is laborious and time consuming.
If there is a mix of Lightspeed and Tomahawk line card in the chassis, you need a SMU for CSCvk63470.
HiI posted a question about this case before: https://community.cisco.com/t5/forums/replypage/board-id/5996-discussions-xr-os-and-platforms/message-id/11819 Unfortunately I could not find my answer in provided link in that post. My scenario...
Hello Everyone,I am trying to configure EVPN service on QinQ double tagged sub-interface. So is such configuration supported? interface Bundle-Ether1.999 l2transportencapsulation dot1q 999 second-dot1q 99rewrite ingress tag pop 2 symmetric!evpnevi 10...
HiI am searching about different types of SFC for ASR99K. In the datasheet it was mentioned this module provides 230Gbps Fabric Capacity and SFC3 provides 600Gbps...There are some questions here:1- Is this value half-duplex or Full-Duplex? I mean does thi...
Hi all, I'm looking for a solution / howto configuration for setting up a SIP trunk between CUCM 11.0 and a SIP-VoIP provider.Got SIP username, password and SIP-proxy IP from the provider. I am not sure how to do it, can I do it without CUBE ( d...